How can I get my text message app back? I accidentally deleted it.

Go to the App Library (the last page of the Home screen), tap on the Search bar, and an alphabetical listing of all apps will appear. Hold your finger on Messages and drag it to wherever you want it on the Home screen.

I can (but it actually cannot be deleted, so it is on your phone somewhere):

• Launch the App Store
• Tap the Search icon
• Enter “Messages"
• It magically appears

And if I tap on it this appears:

You should be able to download and install from the App Store.