Everyone's routine is a bit different, but there's one thing that we all have in common: The need for a good night's sleep. Failing to get the required amount of rest can be the difference between a productive day with a positive outlook and a fruitless, seemingly unending one. Even though you sleep — or try to — every night, it doesn't always get easier with more practice. Sometimes you need an aid to get your eyes to stay shut. We've found eight apps designed to help you squeeze out every last ounce of sleep from an evening, which can help make sure you wake up every morning feeling refreshed.