Apple is going to unveil iOS 13 at its yearly developer conference this June, and today a lot of what's going to be new in it has been leaked. First off, iPhones and iPads will get a system-wide dark mode, that you can enable in Settings, including a high contrast version, similar to what's available in macOS. Oh, and iPad apps that run on a Mac through Marzipan will be able to take advantage of dark mode on both systems. There will be a lot of iPad-specific changes in iOS 13, including the ability for apps to have multiple windows. Each one will contain sheets that are initially...