- It is a very helpful exercise, by working on a large number of muscles in your body, helps abundantly for a fitter you. It helps you to focus on your shoulder, abs, and your lower body, all at the same time. It helps train your muscles to work together and become stronger. - Sit-Ups Pro - Home Work Out! This is a real working app with a Mobile sensor. - This is helpful as a personal trainer. This app not only helps to count the number of sit-ups you do but also calculates the calorie you lose