This free app is all about teaching you how to run according to your heart rate! Pear Train-Intelligence is an excellent way to monitor and control your heart rate and was designed for people who need to focus on that. Although this app is free, the chest-strap, heart rate monitor, earphones, and pouch cost $99. Don’t let that scare you away though, this is an in-depth app for iOS and Android devices and it won’t leave you disappointed! If you do not want to purchase the other equipment, it is an option to use the app by itself. Workouts are available for running, yoga, weightlifting, and more. All sessions include commentary to coach you through to the next step (many workouts also include videos).