iOS 10 reviewed: There’s no reason not to update

By nature, iOS is not a permissive operating system. Apple started from a position of not trusting third-party software developers, fearing those outsiders could screw up the company's platform (a completely reasonable position to take, incidentally). Every new version of iOS since the second one has been very cautious and deliberate about what new capabilities are given to third-party apps.

iOS 10 offers a lot of new stuff for users, including several redesigned apps, a new design for notifications, an improved Control Center, and more. But it's also got a lot of under-the-hood changes for developers in the vein of iOS 8: it opens up notifications, the UI for making and receiving voice and video calls, the Maps app, and Siri, and it re-imagines Messages as a sort of platform-unto-itself complete with its own branch of the App Store.