Hi @長田 俊平,
Thank you for posting in this community.
I tested it based on the description of your problem. Indeed, the column's display by condition does not work on mobile. This seems to be a bug in Microsoft List. I suggest you provide feedback here about this issue you found.
I am sorry we don't have a solution to your problem at the moment. Please accept my sincerely apologize for any in convenience this may cause. Thank you for your kind understanding.
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