While I'm typing this in the Safari browser, I had a quick look at the menus, and everything is capitalised except the words "and", "as", "in" and "to". So while I can't say whether your translator is right or wrong, he or she is in good company. And what's good for a MacOS X application written by Apple is probably good for an iOS application. For Android, hopefully someone has read a style guide for Android and can tell you. An example in Safari is
Bring All to Front
which is just like your translator would have done it.
As I said, I don't know if it is a general rule, but there is nothing to indicate that Apple isn't following a general rule. But be that as it may, the OP's problem is to get translations that are correct in the context of an application running on iOS or Android. And personally I think using words like "consuetude", especially following "typical", don't contribute to making your comment understandable.