iPhone and iPad
7-9 hours for everyone. Even if you’re one of those people who say you don’t need at least 7 hours, research says otherwise (maybe you’re suffering from sleep debt). A few years ago, Apple introduced Bedtime, which operates within their clock app. After answering a series of questions, you can be in more control of your sleep schedule. I use this because I usually get into some sort of evening project, whether it’s reading, writing or exercising, after my kid goes to bed. It’s easy for me to lose track of time, but this little feature politely reminds me when my bedtime is approaching so I can take care of a few things before turning in.