10 Apps That Will Turn Your Apple Watch Into a Sleep Tracker

Cost: free; premium subscription is $30 a year after a seven-day free trial

Can't figure out why you're not feeling as rested as you should be? With Sleep Cycle, you may be able to rule out snoring or sleep talking. The app records any sounds you make while you sleep in order to assess your sleep quality every night — and yes, you can go back and listen.