How can I find hidden app?

Go into the App Store and click on updates, then you will see a bar that says purchased apps and apps not on phone. You should see it there.

You can also use your spotlight search and swipe right on your screen and enter the app name.

You can also just download it again from the App Store and if it's already downloaded you will click open.

Scroll down on the home screen. Enter the app name in the search bar you see at the top.

Try searching the App Store for the app that you deleted. That is if it was an Apple App. If it was a third party app, go to the app store, then updates, then click on the purchased.