How do I recover an app that disappeared when I was rearranging apps

Try searching for it. If it really isn't on the device, then re-sync from your iTunes app.

You can only "open" an app if it's actually installed on the device. Otherwise, you download it to be stored on the device, then run it from the device. When you are looking at the app while in the App Store (on the device), next to the name you should see one of a few things to the right of the app's name:

GET button: the app has not been purchased yet and is free to purchase

Cloud icon button: the app has been purchased but is stored in "the cloud". To use it, you need to tap on the cloud where it will then be downloaded to the device

OPEN button: the app has been purchased and is downloaded and stored on the device.

$1.99 (or some other price) button: the app has not been purchased & is in "the cloud".

What button are you seeing in the App Store on the device? If the button is the OPEN button, then the app is somewhere on the device.

If this is the case, search for the app using Spotlight Search. Tap-drag down from the middle of any of the Home screens, then enter the app's name in the search field at the top.

If you still cannot locate exactly where it is on the device, reset the Home Screen layout under Settings/General/Reset, then tap on Reset Home Screen Layout. This will move all apps out of any folders they may be in, sort the default (non-user installable/deletable) iOS apps on the first Home Screen pages, then alphabetically sort all the user-installed apps on the page beginning with the first blank page after the default iOS apps. Your Home Screen layout will be totally disorganized from how you organized them yourself so be warned.

CarlSparky wrote:

I can open the app this way but how do I get the button back? Or how can I find the button?

See the last two paragraphs in my post above.

Good to hear!