I only use Strava now on my iPhone4. It lets you analyse any section on your ride, with wattage, times, elevation etc. and also detects and compares climbs to your previous rides, and to other people that have cycled the route. Plus, although my commute is fairly short (20km round trip) I've never had issues with batery life, even when riding longer rides on the weekends etc.
Plus, the social aspect of it is amazing- there's a few pros that use our mountains for training, so seeing my times compared to theirs, even just for the climbs, always motivates me to get my head down and get'er done.