I like this app, but I hate its developer.

Ive finished third part of traning till now. Im still angaged, so I can say, it works. But even though I bought full paid version, I still have to watch pop-up ads at the begining. They even prompt me to buy those apps I akredytowanych have. Greedy tighteners.

Radek Niejadek about SitUps to Six Pack - 0 to 200+ SitUps Training, v1.2