The lack of translations has already been mentioned in this forum. In the process of making my REGEXP question type mobile-compliant I have had a look at the core question types and am surprised to find out that a number of translations are missing. When switching the language to French, in the example below for the short-answer question type, the strings I have framed in green are translated but the strings framed in red are not. And the same is true of ALL the question types.
I am surprised that the translations in the desktop version of moodle are not automatically made available to the mobile app.