iOS/Android: We're big fans of Sworkit Pro, the exercise app that generates a custom workout for you based on the amount of time that you have, and the app recently added a few great new features. You can now customise your workouts even more and check out a log of your exercise.
The big new feature here is that you can now change the interval length so you're no longer stuck with 30 second intervals. You can also customise the workout order so it's not completely random every time, which is nice if you find an order that really works for you. Finally, you also get a new workout log that shows what you've been doing and how many calories you've burned.
Sworkit Pro ($0.99) [Google Play]
Sworkit Pro ($0.99) [iTunes App Store]