I had just added touch input that moved a sprite in my app and this worked when testing on the unity remote 4 app. But when I install and run the app on the device touch no longer works. I have also been getting an error saying: “Multiple EventSystems in scene… this is not supported UnityEngine.EventSystems.EventSystem:OnEnable()” which I think is related to this. Here is the relevant parts of the script.
Maybe you have too many ‘Event System’ components in your scene?