Ad Removal purchase missing after uninstalling and reinstalling Fongo for iOS

If you have purchased the Ad Removal package for Fongo and you uninstall the app and then reinstall it, you must restore the purchase from the Add-Ons screen to remove ads again.

If the 'Restore' button does not appear in your app you may have disabled 'In-App Purchases'.

To re-enable 'In-App Purchases' you can do through the Restrictions Settings

 Go to Settings->General->Restrictions

Then turn on 'In-App Purchases'