If I add my smartphone as a presence sensor, can I access the smartphone’s remaining battery through a SmartApp?
The API on iOS devices has an option for BatteryStatus. Not sure about Android. It is an interesting thought. What did you have in mind if you had the ability to get the status?
https://developer.apple.com/library/ios/samplecode/BatteryStatus/Listings/ReadMe_txt.html
@brianlees I am planning on using an old phone as a wall control unit (ST app).
However, I do not have a power outlet near the location I plan to use it.
I was wondering if I can add the phone as a presence sensor, and have ST remind me
when the battery is low.
I have a bunch of ST Multi sensors that report battery status, wanted to know if a
smartphone added as a presence sensor can indicate battery status.
Oh, that’s a pretty good usage scenario. 
I wonder if another tool out there would work. I’m certain you could get a text message if you jailbroke the phone - there has to be an app out there that will do that (pure speculation on my part).
@brianlees Thanks.
You re right, it can be done differently, but was wondering if it can be done in the ST app.
It should be fairly easy to add the ability to access remaining charge on the ST app.
I will add this is as a low priority request on the mobile app forum.