[Palm WebOS] BatteryMonitor

The Pre battery has never been a strong point. As a result, there has been a good deal of guess work on battery life based on configurations. Should I turn off my GPS, should I keep AIM offline, should I keep my cards open, or close them? There really isn't a good way to determine this right now. And what about new OS versions? Most people can only say it seems better.

What BatteryMonitor does is it tracks battery usage over time. Using this tracked information, it can guess how much battery you lose per hour, how much time you have left, as well as illustrate your battery usage in a graph.

The way I do this is by polling for the battery status at defined times, which you select when you first start the application. As a result, the information isn't very reliable until used for an extended amount of time - I'd say a minimum of one hour. Without this larger sample set, the chance that a one-off skewed data point could muck up the results. I suggest using smaller intervals - but you have to keep in mind that polling every 1 minute also has a small impact on battery. With larger intervals, such as 10 minutes or more, you may need much more data before the numbers normalize.

Graphing is implemented via the google chart API. This means that a data connection is required to download the chart after each update. It is normal for the line to look mostly flat at the beginning, again give it some time before judging results.

The notifications option will send a notification with the current battery level, the drain-per-hour rating and the calculated remaining life after each poll. I suggest not using this if you set your polling time anywhere less than 30 minutes because it will become very intrusive. In fact, I'd probably suggest not using it at all.

The application needs to be running at all times to track the data but can be running in the background. So you are encouraged to do day-to-day use while it is running and see how much battery life your current configuration is using.

Feedback is welcome but I don't plan on modifying this application much. Being my first app, it was more of a learning project than anything else. As a result, I want to focus my efforts on more ambitious endeavors.

The code is free to be reused by anyone should they want to, given that it is NOT for commercial use.

For more information about my project please visit my co-blog, futurepr0n |

Download the IPK directly from:
http://www.futurepr0n.com/com.palm.f..._1.0.0_all.ipk

To give some baselines:

My phone has:
- 3 e-mail accounts syncing on 15 min intervals
- Logged into gtalk constantly
- GPS turned on
- Wifi and bluetooth off

Draining
3.7% DPH (drain per hour) idle usage (check time, random text)
30% DPH while browsing on EVDO

Charging
+25% per hour on usb charger



Post your results and configuration!

Screenshots:

can be originally found here:

Code

http://forums.precentral.net/homebrew-apps/202430-batterymonitor.html