Runtastic 6 pack

Options
Has anyone else tried this app out? I ran through solid till level three... Which promptly kicked my *kitten*, so I went back to run through level 2 again. I just added it onto my routine after weights so I do 35 mins cardio, 20 mins weights and 20 mins of this app to strengthen my stomach 6 times a week. Seems to be a fairly decent mix up of stomach exercises so I enjoy it. Anyone else had any experience with using this app?