I strongly feel that before Renshuu is available on the Google store, it should be made simpler to use. Otherwise you could have thousands of people setting up an account, getting confused, and leaving before they find out how great Renshuu is.
Meaning there would need to be additional complexities under the hood. It's probably impossible to see, if you've worked on Renshuu for years and have it all in your mind, but it is rather confusing at first, and there are still things that are kind of bothering to me now due to the fact that at the beginning I didn't understand at all how the site works, and I didn't setup things as needed. I invited a (French Vs Greek) language partner to use Renshuu, as I think it's the very best there is to study Japanese. She tried, but was too confused to start studying at all. She'll try again. I'll start with what still bothers me, then will try a checklist of things that could help (some of which might already exist on the site). Other users might also have additional suggestions?
The reason why you probably have very little feedback, if any at all, is the same reason why no school child tells the teacher that he didn't understand, despite being completely confused by the lesson: he doesn't want to appear dumb. I don't have this anxiety, so I don't mind admitting I'm confused, when it's the case. So here are some ideas to make the site less confusing in some of the most fundamental aspects.
The first thing is, it's not necessary obvious to someone who first comes to the site what is a schedule, why you need to create a schedule at all, and not, say, simply choose the level you want to study, and just start getting quizzed on JLPT N3 every day after that. I'll get back to that.
What still bothers me is related to the studypad. At first I used the studypad to add words from example sentences that I wanted to study, and words that I found elsewhere. But I never understood how to quiz the studypad separately, so when I had just over 100 words in it, I instead created a schedule called "studypad", and I put those 100+ words into it. It works fine. But it's a schedule, not a lesson, so I can't see the list of words in the study center. If it's actually possible to study the studypad separately, how? (a bit too late for me, I'm getting close to 1000 words in the "studypad" schedule, but it could be useful to others to clarify). If a schedule is not made of lessons (like my "studypad" schedule), would it be possible to create a lesson containing its vocabulary, in order to see this vocabulary in the study center? (maybe in blocks of 100 words, if having one gigantic lessons causes some problem). So far, it works only in the other direction, you can create schedules from lessons.
While on the idea of operations on schedules and lessons, It would be neat if I had a way to remove the N3 / N2 vocabulary that is in my "studypad" schedule list. If I could see this word list, and order them by JLPT level (from N5 to "beyond JLPT"), then I would just have to remove what comes at the top, that would work.
Anyway, more fundamental things, now. I don't remember exactly how it is when starting, and you probably changed many things, so here are a few questions, a kind of check-list :
-When the user uses the startup help, does it ask the user his current level?
-If the user has no previous knowledge, does the site setup a schedule "basic vocabulary" containing the JLPT-N5 vocabulary? And a kanji schedule with the JLPT-N5 kanjis, if the user indicated he wants to study kanji.
-Do you have something planned for users who have zero prior knowledge to study hiragana and katakana?
-If the user does have some knowledge of Japanese, does the site setup a schedule containing the appropriate vocabulary, and then offer to also setup a second schedule containing basic vocabulary but with mastery levels pre-setup at the estimated level of the user? Say, if a users indicates going to an intermediate level, studying for JLPT-N3, setup the schedule "JLPT-N3" containing just that, but also another schedule containing N4 and N5 at the estimated mastery levels : "well known" for N5 and "a bit" for N4, or both "well known", or "very well" and "well"… depending on the answers of the user.
-If a user has no vocab or kanji schedule setup, does his dashboard have one big button (or 2) shouting "Create my first [vocab/kanji] study schedule!"?
Hmmm… unless I forgot something, I guess that covers it, that was shorter than expected. (but probably implying an awful lot of work, I guess, unless I missed something and all that is actually already implemented).