With the new support for mice and keyboards on iPads, it is very frustrating that there is no real support in Minecraft. It is especially frustrating when there is a section of the settings dedicated to keyboard controls. It is possible to even change the key assignments, but there is no affect in game.
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We're tracking this issue in MCPE-51263, so this ticket is being resolved and linked as a duplicate.
That ticket has already been resolved as working as intended, which means this is not considered a bug and won't be fixed. Please do not leave a comment on the linked ticket.
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