Meanwhile, I have no idea if battery life impact is worth measuring in your use-case. My assumption would be "no" because I would imagine the battery life impact would vary too widely to yield useful data and I don't see what I could do with that information anyway other than recommend some people not use the app. But I'm not really thinking deeply about it now, so I'd love to be enlightened. Meanwhile, trying to get more customers is a good thing, even if it fails.