Dig Into iOS 9.2.1 Feedback
If you're having a good experience on iOS 9.2 or whatever you're on, it might be a good idea to wait a few hours for initial iOS 9.2.1 feedback to emerge.
If you're feeling a bit leery, wait. Apple won't force you to install the iOS 9.2.1 update. We've put together some thoughts on the iOS 9.2.1 update and its performance and it's worth taking a look if you're currently undecided about its merits.
This is particularly important if you're coming from an older device or if you're coming from something older than iOS 9.2. If that's the case, you'll want to look into iOS 9.2 reviews to get a feel for its performance. This feedback will help you make a smarter decision about iOS 9.2.1.
Remember, you can't go back to anything older than iOS 9.2 once you upgrade to iOS 9.2.1. So you need to be sure.