Read this review first.
The app is good. It doesn’t crash, and it looks nice. There are two things that took off two stars from this, though. One is that sometimes the horizontal ads on the bottom of the screen block the button to go to the next set. You have to forge close the app and then start again. The other thing is that it doesn’t get you to be able to do 20 pull-ups. You chose a level for yourself, then you do all the sets for a week or so. The highest FREE level is level five, which is 12-15 pull-ups. Then, level six is 16-20. Level and up aren’t free! The level five workout does not get you to 20 pull-ups, so you have to pay to get to 20 pull-ups. Be mindful when getting this app!!