Thanks for all the hints!
regarding saving my relatively large project on ipad3: kiosk pro app in combination with iMazing App worked perfectly.
Unfortunately the performance problems still remain. (Sort of infoscreen with lot of small artist pics). Especially swiping and scrolling a bunch of pics at once, the ipad is struggling. Jpgs Pics are at average 30KB each. I thought first the hype filter effects is too much, but deactivating them didn't help. Also starting animation stutters. (Everything super fine on macbook)
Thought maybe the Nexus Tablet will handle it?
Will try WKWebView, thanks to Photics. Only at first view I'm not expert enough for this approach.
If someone is curious here is the hype file with one scene out of the project. The middle part can be swiped left and right - the Song List up and down. Not finished yet.