For me the most useful tests for whether I understand or remember anything on the app is a) in the ‘listening’ sections, can I say the German to myself before clicking on any of the three options (which then confirm whether I got it right), and b) having to type into a blank space without any extra help or prompts. The second of these is only possible for single words, or very simple short two-word phrases. It would be great (!) to have this for every word/phrase in the whole course.
For longer phrases, it’s useful to have the step of simply rearranging words that are already given—it helps to teach word order, and helps to imbed the vocabulary. But at a certain point, it’s really just necessary to have to do that translation ourselves, with a blank line and no hints or reminders.
I’m finding that I have to fabricate these opportunities for myself, having my partner read off the longer phrases in English, and then translating them into German (or at least remembering the German translations), and then she checks my answers. For a paid app, that seems … unsatisfactory!