I made a weightlifting tracker app specifically for coders.

In weightlifting, progressive overload is one of the most important parts of gaining muscle. You should constantly increase weights, reps, use different set schemes, and that will make your muscles grow.

There're many weightlifting programs, using various overloading schemes - linear increasing of weights, some periodic ladder-up increase, switching to different set schemes in case of failures, etc. You can implement all of that in Liftosaur.

It works this way: each exercise may define a bunch of variables, that could be changed when you finish a workout. It could be weight, your 1 rep max, number of successful attempts, etc. You can use those variables in reps and weight values. To update the variables, you define a script, that will change them after you've done all the sets of the exercise. The script may change them based on whether you successfully done all the sets x reps, or if you failed any of the sets.

For scripting, I added a super simple scripting language with JavaScript-like syntax called Liftoscript. It mostly only supports if/else, variable setting, and has some built-in types like numbers, pounds and kilograms.

The app contains a bunch of built-in programs, they all are implemented using Liftoscript, and completely customizable. Check it out!