If you've just downloaded an app and can't seem to find it, don't panic! There are a few simple steps you can take to locate the app. First, check the category it was downloaded from. If there are small app icons, tap them to expand the category and view all the apps it contains. If you still can't find it, go to the iOS App Store and search for the app by name.
If it's installed on your phone, it should appear in the search results. If you find the application installed but it still doesn't appear on your home screen, you can uninstall and reinstall it. It's also possible that the app has been removed from the App Store by the developer or Apple (as was the case with Flappy Bird and Fortnite). If this is your situation, open all the application folders on your iPhone's home screen and look for the missing app inside them.
The easiest solution is to swipe down while you're in the app library, which will display a list of all apps in alphabetical order. This way, you can quickly locate any app you've downloaded.