I’ve seen this problem a lot, but Minecraft will not load past the mojang logo on my device, and it seems like this is a problem shared by many others. My device and the Minecraft app are as up to date as they can be, Minecraft being the most recent update. But the app description says that it is compatible with iOS 8.0 or up. I would really like to see this bug fixed so I can use it on my older device, because I paid for a realm so I could transfer over all my old worlds but it seems like I won’t be able to do that.
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Thank you for your report!
We're already tracking this issue at MCPE-54465, so I will resolve and link this ticket as a duplicate.
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Your device might be too old to work with the program minecraft is built with.