RunDouble Couch to 5K goes way beyond any other Couch to 5K app! It is a complete training companion, starting with the Couch to 5K plan, and taking you right through to half marathon. Couch to 5K by RunDouble is the easiest way to meet your goal, of running 5K in just 9 weeks, but don't feel daunted, you can take longer if you need.