Minecraft will not start

My son can't open Minecraft. It is just a picture Majong, and then  a quick green image before everything stops. I think he tried to install some resourcepackages, and now we are afraid he have lost several years with hard work..

When I copy the folders from the ipad to iphone, the same happens with iphone

Could anyone tell me how I can resolve that? Is there any folders I can remove in the package?