Notes:
1. I do *not* have BB Messenger installed.
2. I keep the GPS receiver off unless I really need it.
3. I have screen brightness set to 50. Which is definitely bright enough (compared w/ previous BB devices)
4. I *rarely* watch videos (one day out of 20) or listen to music (one day out of 10).
Email is consistent (20-60/day) and phone calls are minimal (20-40 minutes/day).