It seem that Moodle Mobile doesn't handle quiz behaviours other that deferred feedback.
For example, if you set Adaptative or Interactive with multiple tries, it behaves like deferred feedback in the app. There is no check button showing.
This was reported on Moodle 4.1.6. I also tested on qa.moodledemo.net (4.3).
Moodle Mobile 4.2.0