Strava
Strava is the perfect app if you love running or walking. Granted, this isn’t a workout app, per se. Instead, it’s an app that will help you keep track of your outside workouts.
Whether you like hiking, cycling, or running, Strava can keep track of all your workouts. Moreover, once it has enough data, you can use Strava to compete against your best times in the past.
This will help you stay motivated and become better at walking or running. Or, if you like some actual competition, you can use Strava to compete against other people who have gone through the same routes you’ve used. You can start a friendly competition and maybe even meet people with the same goals.