great idea, unfortunately droidwall requires rooting your phone. I'm not criticizing anyone that does it, i just don't have any intentions of doing that myself.

i downloaded a game that requested GPS and network info -- the dev's website stated that it was used by the ads to target audiences. In such case, it'd be great to turn off those features for that specific app. Now, if a PAID app asks for such things, then you should definitely question their motives.