I have a Holux GPSlim 236 bluetooth GPS receiver that I want to use with my GS2 when I go mountain biking instead of the internal GPS as that would drain the battery too quickly.
I've successfully paired the receiver with the GS2 but none of the apps (Tracker, GPS Test, Maps, etc) actually "see" the external gps receiver and just display no lock and don't show any satellites. Switching on the internal gps receiver makes everything work as expected.
Is there anything special I need to do with the external receiver and pairing it to the GS2? Is there a setting buried in Android somewhere that directs all GPS apps to use an external receiver? On the old WM6 platform you could choose different com ports for the receiver but I see no options in android for that.
Never mind. It appears you need an app (yet again!) to do this. I installed blue4droid and it works now. Why isn't this functionality part of the core Android OS?
sunseaker said:
Never mind. It appears you need an app (yet again!) to do this. I installed blue4droid and it works now. Why isn't this functionality part of the core Android OS?
Click to expand...
Click to collapse
Very few people ask for this feature (first time I've seen a request). Your need is very specific, are you sure you will save much battery with a BT-link constantly running?
Older platforms like Symbian S60 and WMP6 supports this quite obviously since this was the only way to get GPS on many older smartphones, but on Android almost all phones have GPS from the beginning.
This seems like good example to me where a dedicated app is better than making the standard Android OS more complicated.
Please remember that more or less every app in the market fulfills purpose for a certain number of people, that doesn't mean that all these apps should be included in the OS...
I hear what you're saying but I'd be surprised if BT used as much battery as the GPS. I took the GS2 out for a test yesterday on a short 1.5 hour mountain bike ride with the internal GPS on and it drained 50% of my battery. A lot of my rides are usually a lot longer in the 4-5 hour range so the battery will never last.
I assume BT will use a lot less power but I have yet to test it which I'll be doing in the next few days.
As for it not being a common feature request, I guess that you are right when taking into account all the Android devices around but it's actually quite commonly asked for in the cycling and running world where you want to track your path and other parameters during your training. the phone batteries just cannot cope with powering the internal GPS for more than a few hours.
I don't mind using some apps to enhance the OS but I just feel with Android it seems expected that you need to bolt apps on to achieve what normally is basic functionality. Also a lot of the apps require permissions to parts of the phone that have nothing to do with the functions the app is providing. I'll concede that perhaps in this case an app would is suitable than having the functionality in the core OS.
sunseaker said:
I hear what you're saying but I'd be surprised if BT used as much battery as the GPS. I took the GS2 out for a test yesterday on a short 1.5 hour mountain bike ride with the internal GPS on and it drained 50% of my battery. A lot of my rides are usually a lot longer in the 4-5 hour range so the battery will never last.
Click to expand...
Click to collapse
50% in 1.5h sounds a lot.
I don't think this is because of the GPS, what app do you use to log the position? Does it keep the display on all the time?
I haven't checked battery when I've been logging that careful because it hasn't been a problem, but I can see that I have a 3.5 hours log in my track-list and I remember that I checked the map a lot as well during that hike. I'm pretty sure I wasn't close to draining the battery.
Modern GPS-chip doesn't use that much battery, people are overexaggerating the drain from GPS-chip, probaly because of problems with older chip designs. But a lot of software that uses GPS, e g car navigation system are often huge battery hogs though.
I've read that this is the chip inside SGS2:
http://www.csr.com/products/25/sirfstariv-gsd4t
It seems to use 8mW with 1hz update. So the battery in SGS2 can run only the GPS chip for (4V*1650mAh)/8 = 825hours...
So I believe the battery problem you have is caused by something else, so adding an external GPS might not solve anything at all.
Hmm, that throws a different light on it. I'm using Run.GPS for my tracks. I'll have to monitor this more closely and try a different app for comparison. What did you use for tracking your hike?
The app isn't keeping the screen on and I physically turn it off with the power button anyway. The app is also set not to illuminate the screen back light although I don't think it makes any difference with the AMOLED screen.
I'll try a comparison with the external GPS and see how much difference there is to try establish if the app is at fault. I expect tracking using the external GPS to use significantly less battery so if battery drain is still high then it points most likely to being the app at fault - we'll see.
Is there any app that can list the various apps / processes that are running and show how much cpu is being used? I want to see how much cpu power the tracking software is consuming.
sunseaker said:
Hmm, that throws a different light on it. I'm using Run.GPS for my tracks. I'll have to monitor this more closely and try a different app for comparison. What did you use for tracking your hike?
The app isn't keeping the screen on and I physically turn it off with the power button anyway. The app is also set not to illuminate the screen back light although I don't think it makes any difference with the AMOLED screen.
I'll try a comparison with the external GPS and see how much difference there is to try establish if the app is at fault. I expect tracking using the external GPS to use significantly less battery so if battery drain is still high then it points most likely to being the app at fault - we'll see.
Is there any app that can list the various apps / processes that are running and show how much cpu is being used? I want to see how much cpu power the tracking software is consuming.
Click to expand...
Click to collapse
I'm using my "tracks", it is an pretty good (but simple) app, but it does not do any GPS filtering, så especially data like max speed tend to be incorrect.
There are definately app's to check processes, but I don't know which is the best, I believe System Tuner Pro is good:
https://market.android.com/details?id=ccc71.pmw.pro&feature=search_result
I tried Tracker but preferred a more cycling specific app.
Thanks I'll look at that System Tuner app.
Related
I have searched the market and google, but I can't find anything that will work with my specific scenarios. I want a rules based app, if it exists, to activate gps when certain programs are launched, like Navi, or maps, etc. Then, the biggest reason I want it, is because I would like it to deactivate on close. I have a real bad problem of remembering to kill it when I am finished using it, so I end up killing the battery prematurely because of my own stupidity. I've tried my phone my rules, and two or three others, but I couldn't figure out how to set it up to do what I wanted. Maybe I'm just an idiot. who knows. Thanks for any advice.
1454 said:
I have searched the market and google, but I can't find anything that will work with my specific scenarios. I want a rules based app, if it exists, to activate gps when certain programs are launched, like Navi, or maps, etc. Then, the biggest reason I want it, is because I would like it to deactivate on close. I have a real bad problem of remembering to kill it when I am finished using it, so I end up killing the battery prematurely because of my own stupidity. I've tried my phone my rules, and two or three others, but I couldn't figure out how to set it up to do what I wanted. Maybe I'm just an idiot. who knows. Thanks for any advice.
Click to expand...
Click to collapse
Cyanogen has profiles like that, but I don't think it extends to GPS.
I've pretty much always run sense ROMs and I ALWAYS leave my GPS checked on. It only uses it when I'm using an app that needs it. I'm not sure where the idea came from that if GPS is left on it will use it all the time, but I've never seen evidence that is how it behaves. Unless AOSP is weird and does try to lock all the time or something....
I use Easy Profiles and like it a lot. It takes a little work to understand but is very useful and really helps me save my battery.
As the previous poster says, most apps turn off GPS when they are deactivated.
loonatik78 said:
I've pretty much always run sense ROMs and I ALWAYS leave my GPS checked on. It only uses it when I'm using an app that needs it. I'm not sure where the idea came from that if GPS is left on it will use it all the time, but I've never seen evidence that is how it behaves. Unless AOSP is weird and does try to lock all the time or something....
Click to expand...
Click to collapse
+1
Stock rom and I leave my GPS on 100% of the time.
I get from 12 hours to well over 24 hours of battery depending on how I use the phone. The GPS power turns off if no software is hitting it for a location.
Turning off the GPS (or WiFi for that matter) has never changed my battery life.
Maybe I'm mistaken then. It just seemed like my battery died off quicker after using Navi. But I didn't actually do anything to verify this. I will also try easy profile as one poster suggested.
1454 said:
Maybe I'm mistaken then. It just seemed like my battery died off quicker after using Navi. But I didn't actually do anything to verify this. I will also try easy profile as one poster suggested.
Click to expand...
Click to collapse
I'd suggest before adding another app that will CERTAINLY eat more battery, to take look at what apps ore services are eating power, and exactly how they're doing that. Even the basic battery stats displayed in stock Android will give you a rough idea. Something like JuicePlotter will highlight what and when certain basic functions eat power. If you're GPS is running, it will stick out as a different color blur coming off the power plot line.
I'm a strong proponent of power management through strategy, not brute force of apps managing it. Kinda like a bank with a good security system... it makes more sense to design the building well, rather than hire guards/apps to do the job at a higher cost in dollars/watthours.
I use Battery widget to monitor my juice usage, but it just "seemed" like my battery usage was worse with GPS on. But I don't use my phone in the same way any two days in a row, so it was probably just in my imagination.
1454 said:
I use Battery widget to monitor my juice usage, but it just "seemed" like my battery usage was worse with GPS on. But I don't use my phone in the same way any two days in a row, so it was probably just in my imagination.
Click to expand...
Click to collapse
If GPS is constantly on being used to update traffic, geotag photos, or track you on GPS, you're going to usually notice sharp drops in battery life. I use the battery widget too, but JuicePlotter can better illustrate where the power is going.
I'm a little surprised noone suggested Tasker, Locale, or SettingProfiles since they will all do exactly what the OP wanted and more. Tasker isn't as user-friendly as the others but seems to provide more functionality. I currently have it set just as the OP wanted. Turns gps on when Maps, Nav, etc open then turn it back off on close. Probably unnecessary but doesn't cause any problems for me so it's fine.
thanks A0. I will definitely check that out, as I think it will work for the other things I wanted to try too.
does leaving the gps on actually kill battery life more? I was under the impression that even if you leave gps on, its only used when an application uses and when it is finished, it turns off by itself. please correct me if i'm wrong.
kwazytazz said:
does leaving the gps on actually kill battery life more? I was under the impression that even if you leave gps on, its only used when an application uses and when it is finished, it turns off by itself. please correct me if i'm wrong.
Click to expand...
Click to collapse
I leave GPS, Bluetooth and wifi on all the time and only loose about 1% battery per hour in standby.
I too would like to know this, it makes sense to me in theory.
Im going to say it doesn't kill battery unless you use it. Based on test ive done myself using "wireless networks" for location actually drains battery faster than just using gps. GPS only activates when its needed and turns off after a few secs; mobile networks is ALWAYS updating your location thus killing the battery faster. Ive done this test for years on many android devices and it was same results. Like i said, i may be crazy but thats my theory on it....
http://img845.imageshack.us/img845/1046/20110911195533.jpg
The GPS receiver remains in "standby" if you turn it on but aren't actively using an app that requires it. Assuming you are using an application that requires the GPS receiver to be on, most likely the screen is going to be on as well. Even in this "on" configuration, the display is going to be the battery drainer, not the GPS receiver. Standby just means that the last position fix is retained for faster sat lock the next time around. GPS standby is identical to GPS off in power requirement.
I never did understand why people disable GPS, Bluetooth, etc. You might get an extra 12 minutes out of a single charge by doing so. I'd rather have instant access to location-based search, Bluetooth headset use, and everything else that makes a smartphone, well, "smart."
kennypowders said:
Im going to say it doesn't kill battery unless you use it. Based on test ive done myself using "wireless networks" for location actually drains battery faster than just using gps. GPS only activates when its needed and turns off after a few secs; mobile networks is ALWAYS updating your location thus killing the battery faster. Ive done this test for years on many android devices and it was same results. Like i said, i may be crazy but thats my theory on it....
http://img845.imageshack.us/img845/1046/20110911195533.jpg
Click to expand...
Click to collapse
i think you may be right, as if you just leave wireless/mobile networks on and not gps, when you use your google maps you dont get the gps icon on the top so you dont know when its actually on or off. whereas if you have only the GPS checked you will see it on when its being used and off when its not.
I'm thinking of buying a GS2 and was curious when I read the review below on Amazon. In particular, the comments in points 1 and 3 regarding CPU/battery usage are a little worrying. Does anyone here agree/disagree with this?
**** 8 WEEK UPDATE ****
Having had this phone for two months now I thought I'd update this. There are several things now about Android and the GS2 in general that are now apparent to me and may be deal-breakers for some of you, though it should be noted that most of these are applicable to all Android phones, and not just the GS2:
1. If you use your phone as your primary music player (e.g. like an iPod) then this is NOT the phone for you - it (as far as I can determine) has no dedicated hardware to decode audio and so it uses a lot of CPU power to play music. The phone will get very hot in your pocket from the CPU heat and within 4 hours the battery will be completely dead. This turned out to be a deal breaker for me as I use my phone extensively for music playback, and the iPhone is still the only phone I know of that gives 40 hours playback.
2. Gapless audio playback is not supported by Android, though some players buffer the next track to simulate the feature (e.g. PowerAmp) if you're willing to pay for them. Gapless playback may be supported in future Android versions, though I don't know how or when one could find out exactly what version of Android will support it.
3. There is a very common bug in the GS2 whereby an application called 'Wifi Sharing' will randomly start itself in the background and consume a huge amount of CPU power (doing nothing) and drain your battery SEVERELY. Your battery will be dead in 6 hours if you don't 'force close' the application. The only solution at the moment if you have this problem is to install something like WatchDog Lite and set up an 'alert' to warn you when Wifi Sharing starts to overtake your CPU so that you can 'force close' it.
4. For all of Android's beauty and the Touchwiz inteface Samsung has put on top of it, I've become aware of some quirks of Android, especially relating to the (VERY) inconsistent use of the menu button. Many applications use this button differently (or not at all), showing different menu items on this button depending on what screen/section you are in on the application. It's definitely not intuitive in this regard compared to iOS, though some applications do use it appropriately and in a logical manner. On the other hand, the 'back' button is fantastic and I think Apple should employ one in their phones, too.
5. Screen burn-in. I've not seen many posts about this around the intertubes, but there is what can only be described as burn-in visible on the notification/status bar of the phone when you are using an application that hides the bar (e.g. having a white section where the status bar would otherwise be displayed). It looks exactly the same as burn-in looks on a plasma television; a slightly dark/grey area where the reception indicator, clock, and other indicators normally display. I suspect this is related to the super AMOLED plus screen technology though most people will probably never notice it - if they did it would be discussed in forums all over the internet.
6. Complications with applications are frequent. Unfortunately it would seem the Android market is severely fragmented due to the shear variety of different Android hardware (i.e. handsets) available. Almost every app you download will have comments attached saying things like 'won't work on HTC Desire... ' or 'If you get the so-and-so issue then uninstall, reset and reinstall' etc., etc., Coming from iOS, this is rather jarring and definitely does not fly on a 500GBP product. Furthermore, with the exception of the very common/popular applications, you are very likely to encounter flakey apps that consume too much battery power or randomly crash/force close (or 'FC' as it's commonly called in the Android community)
7. Speaking of battery power... In my initial review (below) I mentioned how awesome it is to have widgets on the home screen. This remains true, but generally at the expense of battery life. This, combined with the battery drain experienced when using the phone for audio playback will very quickly drain your battery. You will be lucky to last the working day if you also use the phone on the road to receive and respond to emails in addition to your music, surfing, widgets, etc. This may be considered an acceptable trade-off, but no one warns you of it beforehand (at least I wasn't aware of it, and just assumed I'd still get at least a full day out of the battery). I've since learned Android phones have a horrible reputation for poor battery life. Expect to last around 12 hours with medium-light use.
With all the above said, this remains an outstanding phone and by all accounts one of the very best phones available on the market. It is super-fast - faster than my laptop - and the physical design is beautiful. For any existing Android user this phone is a dream. For people coming from iOS, I hope the above update has warned you of some of the limitations on this otherwise outstanding product.
i read it on amazon and laughed my sgs2 is the best phone ive owned if you read the futher reviews people argue his points mate
buxz777 said:
i read it on amazon and laughed my sgs2 is the best phone ive owned if you read the futher reviews people argue his points mate
Click to expand...
Click to collapse
Is the comment regarding audio playback accurate? (i.e. the lack of dedicated hardware results in excessive CPU usage and battery drain)?
Sounds like an apple employee got bored...
The SGS2 is great for music playback. I use mine every day in work, for 8 hours and only ever get down to about 50%, and that's with some web browsing thrown in and texting.
Also, i thought it decoded most if not all audio formats fine? I have mp3, wav and flac files in my playlists and no problems there at all.
On my one hour daily commute..i listen to music plus screen on time at like 60% full brightness when i switch between songs whilst browsing between my news and football apps..and i probably use about 10-15%.
Wifi sharing annoys me..but i didnt notice extra large battery drops.. when i first got my phone i had wifi on all the time and it was fine. Since then i rooted my phone and 'froze' wifi sharing...so when my wifi is on...i don;t have to worry about it.
The super amoled screen gives this phone an edge on battery life above other android phones even though it still isn't as good as i hoped. And the standby time is really good.
Remember iphone battery is not removable so once you ruin it with the inevitable half charges and overnight charges your in the sh*t. You can atleast buy a spare battery for androids and keep it in your back pocket. lol jus read what i wrote...this phone has turned me into a bit of a fan boy
itm said:
Is the comment regarding audio playback accurate? (i.e. the lack of dedicated hardware results in excessive CPU usage and battery drain)?
Click to expand...
Click to collapse
i dont understand this the sgs2 has a dedicated yamaha audio chip it isnt running as good as the wolfson from the sgs1 but it is still pretty decent in terms of audio quality
as for cpu useage and excessive drain on the battery i use music all day at work and its fine , it doesnt get hot , it doesnt drain battery badly , it doesnt run cpu at maximum
i use my sgs2 as my main audio device as i have bluetooth stereos in the car and home and some ok headhones from work and i dont have his troubles at all
itm said:
Is the comment regarding audio playback accurate? (i.e. the lack of dedicated hardware results in excessive CPU usage and battery drain)?
Click to expand...
Click to collapse
The sound card is different from the SGS1, which was considered more efficient. This is why a few sound amplifier apps refuse to work with the SGS2 (Voodoo Sound) etc.
Obviously Samsung decided to cheap out on that aspect.
I have not seen any color burn ins, or anything like that.
You have to remember that people who dont like a product are more likely to write a review .Saying that i use Amazon reviews to get an idea about a product or alternatives a lot before buying .
jje
I am really starting to loose my patience with the prime, I have had it for a week now and its just been a very a difficult ride so far. Coming from the original iPad, I never had any problem with it. For some reason, I lost 20% of my battery just surfing the web last night, now I did not view any videos, I was just reading several online newpapers. 20% in an hour !!! what the hell is going on here.
Can sombody recommend me a decent battery monitoring app pleaase? otherwise, this thing is going back and then I will have to beg Apple to take me back.
How many things do you have syncing? Cutting down on that saved me a lot of drain. Also the app you use depends on what you're looking for.
Where's my Droid power seems quite useless on the prime
Better battery stats is good for finding apps with wakelocks
Current widget is good for tracking the current your tablet was using but I'm not sure if it works on he prime
Good luck!
Sent from my Inspire 4G using xda premium
lucky6877 said:
I am really starting to loose my patience with the prime, I have had it for a week now and its just been a very a difficult ride so far. Coming from the original iPad, I never had any problem with it. For some reason, I lost 20% of my battery just surfing the web last night, now I did not view any videos, I was just reading several online newpapers. 20% in an hour !!! what the hell is going on here.
Can sombody recommend me a decent battery monitoring app pleaase? otherwise, this thing is going back and then I will have to beg Apple to take me back.
Click to expand...
Click to collapse
What brightness was your screen set to? Did you have SuperIPS turned on? 20% seems excessive but having the brightness cranked up can noticeably impact battery life, and using SuperIPS nearly triples the drain.
FWIW I keep my screen brightness to about 30% most of the time and I surf the web for about an hour or two a day and I have been getting 3-4 days of battery life or more. I leave the tablet turned on all the time as well, and last night after 3 days I plugged it in because the battery had finally reached 50%.
lucky6877 said:
I am really starting to loose my patience with the prime, I have had it for a week now and its just been a very a difficult ride so far. Coming from the original iPad, I never had any problem with it. For some reason, I lost 20% of my battery just surfing the web last night, now I did not view any videos, I was just reading several online newpapers. 20% in an hour !!! what the hell is going on here.
Can sombody recommend me a decent battery monitoring app pleaase? otherwise, this thing is going back and then I will have to beg Apple to take me back.
Click to expand...
Click to collapse
My Battery Drain Analyzer is good if you want to see an ongoing indication of how much battery is being drained per hour. https://play.google.com/store/apps/details?id=com.WazaBe.android.BatteryDrain&feature=search_result
However, in order to characterize your battery use as good or bad, we'd need to know the brightness you were at (as others have mentioned), whether you're running Flash on the sites you were visiting, what performance mode you have the Prime running in, etc. Too many variables.
I'll add that it's difficult to compare an iOS device and an Android device in terms of battery use, because the Android device is likely doing much more in the background. There's a tradeoff between functionality and battery life (and between functionality and simplicity, etc.), and of course in such an equation Apple ALWAYS opts for reduced functionality. That's not necessarily a bad thing, but it's definitely Apple's approach and has to be factored into any comparison.
I do burn about 15%/hour when browsing, on 30% brightness or so and in Balanced performance mode. I've found the Prime to be excellent in battery use everywhere BUT browsing--video about 10%/hour, email/ebook reading/etc. bout 7.5%/hour, etc.
Thank you all for your comments. My brightness level is set to 20% and gps, bluetooth all set to off. I am now using auto airplane mode app and it has significantly improved the battery life. I am also now using a fantastic app called android assistant and i spotted services that were running like google+ and google voice search which were consuming a significant portion from my battery.
Links for apps i mentioned:
https://play.google.com/store/apps/details?id=com.advancedprocessmanager&hl=en
https://play.google.com/store/apps/...vbS5ibG9nc3BvdC5kb25rdW4zLmF1dG9haXJwbGFuZSJd
I clicked the thanks button for every response.
Sent from my Transformer Prime TF201 using Tapatalk
The best battery monitoring tool I've found is Battery Monitor Widgit.
And I would highly recommend Tasker over any app that is dedicated to turning a single function on or off. If, that is, you are willing to learn to set it up. You can do things like have it set screen brightness to max when you start YouTube and set it back down to your preferred setting when you exit YouTube, turn WiFi or GPS on or off based on certain criteria, etc, etc, etc.
A simple free alternative to Tasker that I use is AutomateIt. The most rules are set on my phone to turn antennas on/off and manipulate volumes while I'm at work, driving, or at the gym. If you're looking to do more complex thing, Tasker is probably the better alternative.
Col.Kernel said:
The best battery monitoring tool I've found is Battery Monitor Widgit.
And I would highly recommend Tasker over any app that is dedicated to turning a single function on or off. If, that is, you are willing to learn to set it up. You can do things like have it set screen brightness to max when you start YouTube and set it back down to your preferred setting when you exit YouTube, turn WiFi or GPS on or off based on certain criteria, etc, etc, etc.
Click to expand...
Click to collapse
+1 for tasker, make life very easy once you set it up....
Col.Kernel said:
The best battery monitoring tool I've found is Battery Monitor Widgit.
And I would highly recommend Tasker over any app that is dedicated to turning a single function on or off. If, that is, you are willing to learn to set it up. You can do things like have it set screen brightness to max when you start YouTube and set it back down to your preferred setting when you exit YouTube, turn WiFi or GPS on or off based on certain criteria, etc, etc, etc.
Click to expand...
Click to collapse
Thanks for the tip about Android Assistant. It seems very useful!
However I would get rid of Auto Airplane mode, you don't need it.
Instead go into "Settings > Wifi > Advanced (top right menu)" and change the "Keep WiFi on when asleep" setting to "only when plugged-in (recommended)" or "never."
What this does is that any time the screen is off, but you are not currently downloading a file or app, the WiFi will be suspended until you turn the screen back on.
You can turn GPS off from the settings if you never plan on using it, and it doesn't make sense having an extra app running in the background that just duplicates functionality already found in the OS.
I never used to mess with things like Llama because of my worry about battery life with previous phones. Now that I have the note, I don't really worry about it anymore. So, with that being said...
Just thought I would throw this out there, that I am enjoying Llama quite a bit. The premise is that you create location profiles - so when you are at home between 7am and 11pm, sound is full volume, etc. From 11pm to 7am, phone is on silent (except for contacts you put on the 'noisy contact' list). When you are at work, you can have a separate profile.
It uses cell towers to determine whether you are at work, home, or wherever else, which is supposed to use less battery than GPS. Even if it does use battery, with the note II battery life, I can't tell a difference at all . Granted, there are some downsides - it is not super-accurate on location. My work cell tower has me until a decent ways off the work campus. But overall it is good enough for what I need it for.
Does anybody here use it? I was also going to try out tasker, but it's a paid app and looks like it requires a decent bit of effort. It supposedly will do pretty much anything though.
does it give you the option to use GPS to assist with location? Seems it could work similarly to a weather app, only triggering gps for a few seconds every 10 or 15 minutes to determine location.
Yup, it does allow GPS in the experimental settings. Not sure if it constantly pulls GPS or only in intervals.
People use llama to save battery, but it drained mine (I've tried it on a few phones, the RAZR Maxx was was the last one I tried). One thing I'm excited about is tectiles, same effect without a drain on the battery.