safari has disappeared from iphone home screen...how do I add it back

It's a pre-installed app and therefore cannot be deleted so you may have inadvertently moved it onto a screen or into a folder, check utilities. Check all screens and folders and do a search in Spotlight, it will tell you if the app it still on your iPhone but unfortunately not where it is. If you find it on one or your screens or in a folder, press the icon until it wiggles and then drag it back to where you want it. Alternatively you can reset your home screen in Settings>General>Reset>Reset Home Screen Layout. Also check restrictions, Settings>General>Restrictions>Safari>ON

Check Settings>General>Restrictions and make sure that Safari is set to On. If it is, look on all your screens and inside all your folders as you can't delete it. If you still can't find it go to Settings>General>Reset>Reset Home Screen Layout. This will restore the home screen to its original configuration but may move other apps around to do so.

For me too.

No Safari icon in any folder or any screen. Restriction is turned off, but turned it on as well and enabled Safari.

Safari is no longer available.

i have no other idea than resetting the device.

No Safari is really gone.