I am writing an app to evaluate the feasibility of a Bluetooth P2P network on Android.
I noticed that on a Galaxy Nexus, it uses very little battery, while on a Nexus S, it drains the battery very quickly. This is directly caused by high CPU load due to Bluetooth.
Now, I would like to collect information about how much battery drain my app causes on the devices it is installed upon. Simply logging time vs. battery level is useless since I don't know when the device is in use, and even if I logged that, I would not know if the user is playing 3D games while Torrenting over WiFi or reading an eBook on a dimmed screen.
To make the problem worse, not all battery usage caused by my app is attributed to it in the battery screen - some is listed as "Bluetooth", for example (again, device-dependent).
Is there any easy, privacy-preserving way to get useful information on non-rooted devices? The devices are not under my control. I cannot simply go look in the menu, I cannot use ADB.
The Android API doesn't support this currently. The only available documentation is the one describing how to use BatteryManager's broadcasts, which only supply the overall battery level and no per-application details.
I suppose that even if there are undocumented ways to emulate what the System Settings battery manager shows, they would require rooting.
AFAIK there is no way to do this. The closest you can get to doing this is to hook up the device to a monitoring tool like little eye labs which does draw the battery consumed by your app over time on a graph. It also supports marking key events in the app's lifetime like turning on WIFI / bluetooth etc.
There is no support for doing this remotely, but you can get the data on your own test devices.
This approach is quite crude, but it may help. You can use the existing BatteryManager broadcasts to track changes to the overall battery level while your app is active.
Knowing when your app is active is a separate issue. If your app consists entirely of Activities, then you can get good results by starting to track whenever any of your Activities' onResume() methods is called, and stopping tracking in onPause(). If you can have all your Activities derive from a single base Activity class, then this is quite easy. See How to detect when an Android app goes to the background and come back to the foreground for suggestions on how to track this.
If your app is more complex, and the smart stuff happens in a longer-running component like a Service, then it's much harder.
This is crude, but at least it would help you distinguish "playing 3D games" from "using my app".
