Nike Training ClubFREE
The Nike Training Club is among the best personal fitness apps in the iTunes store … and it's completely free. For the bargain basement price of zero dollars, you get planned workouts for your full body for 30- or 45-minute sessions; targeted 15-minute sessions; rewards, including workouts from celebrity personal trainers; drills; the ability to customise your workout music from your own library; step-by-step or video instructions; progress tracking; and the ability to share via Facebook and Twitter.
If you have a couple of bucks to spare, also check out Nike+ GPS
(AU$1.99); or for some aural motivation, Nike BOOM