In the past we’ve explored smartphone apps that help you log your workouts and progress. This month we look at four apps, all for the iPhone, that cover diverse aspects of working out.

■ Gym Finder (free) is helpful when traveling because it uses GPS to list and map nearby gyms, showing their distance from your current location and their phone number.

GymKit ($1.99) combines two useful features: a configurable rest timer to precisely time your rest between sets and a one-rep max calculator to determine your maximum single in any exercise.

■ iWorkout Muse ($2.99) sets the duration of interval training and rest periods and then either plays your tempo-adjusted music accordingly
or voice instructions tell you when to start or stop. Great for high-intensity interval training cardio.

Tempo Magic Pro ($4.99) plays songs that are at a 
similar number of beats per minute, so you can match the tempo of your tunes to your cardio or weight training.