No, I'm not talking about the iPhone X. I'm talking about popup views. About every app has to have a few popup modals. Yeah, they are annoying to the user and should be avoided if possible, but there are several important concepts you need to understand to make them less of a distraction. For instance, just because a user can touch the background of the view to dismiss the modal doesn't mean you can leave out the "X" to close the modal. These little tidbits are gold for devs who may not be UI or UX experts.
If modals, dialogs, pop-ups… whatever you want to call them are a necessary evil for transient content, we need to build accessible escape hatches.
Tap to Dismiss by Linzi Berry
Need a refresher on some of the simple built-in animations you should be taking advantage of? Look no further than this post from Theo about UIView animations. Also, part 2 is now out (link at the end of the post) and gets more advanced with CoreAnimation.
iOS Animations: UIView (Part 1) by Theo Ben Hassen