Set Updates to Automatic
You probably don’t like Apple hassling you about software updates all of the time. And while you can just ignore those prompts, it’s recommended that you keep your iPhone or iPad as up-to-date as possible. The solution is Automatic Updates.
Open Settings and tap General and Software Update. From here, switch Automatic Updates on. Your iPhone will then try to download and install the latest version of iOS, normally when you’re sleeping. It’s also a good idea to keep your apps automatically updated by going to iTunes & App Store and switching up the toggle next to App Updates.