Company Zen Labs created these great apps:
C25K® 5K Running Coach & Map, C25K® 5K Trainer Pro, 10K Trainer by C25K®, 10K Trainer Pro by C25K®, Half Marathon 13.1 Trainer, Marathon 26.2 Trainer by C25K®, Push ups (Chest) Trainer Pro, PushUps Trainer Pro - Exercise for PINK, Abs Trainer - 6 pack Workout, Abs Trainer Pro - Exercise for PINK, Weight Tracker Journal Pro, Legs Workout Trainer, Legs Trainer Pro - Exercise for PINK, Butts Trainer - Glutes Workout, Butts Trainer Pro - Exercise for PINK, Push Ups Trainer Challenge, Weight Tracker - Fitness Journal, 0-200 Situps Trainer Challenge, 0-200 Squats Trainer Challenge, Pedometer Free - Runner's Buddy - GPS Step Counter, Pedometer Pro - Runner's Buddy - GPS Step Counter, 20 Pull Ups Trainer Challenge, 7 Minute Workout by C25K®, Sleep Sounds - Alarm & Timer, Zen Sleep Cycle Clock, Track My Steps - Pedometer, 5x5 Workout Pro - Zen Labs, Zen Sleep Cycle Alarm Clock, 7 Minute Workout Pro by C25K®, Track My Steps Pro - Pedometer, Sleep Sounds Pro - Alarm Timer, 5x5 Workout - Zen Labs, 5/3/1 Workout - Zen Labs, RunMate - Trainer and Tracker, Fit Trainer: Easy Home Workout, and others..