As far as I know all of the core features are free. You don't really need to wait for lessons either, that's just how they are set up by default. I have lifetime Pro, but I only got it to support the platform, not because I wanted any features.
You're not made to wait or pay anything. The paid side of things functions the same way. That's no different. The only difference is the content.
On both sides, what you'd see is that you may have schedules that have quizzes available to do (sometimes more or less than what you'd typically practice), but always, always after that's over with, you can repeat quizzes with the "focused review" button. There's no limit to this other than how you've set it up and how much content you have in the schedule. That is it.
I’m almost certain that everything available on Renshuu is immediately accessible for free, without any waiting or payment required. The Pro version offers some useful but not essential features, such as the ability to listen to questions for sentences and sentence questions for vocabulary.
Renshuu stands out as the app with the most comprehensive and in-depth information on grammar, lessons, vocabulary, instant community feedback, and more, all available for free. It truly is a blessing for anyone interested in learning Japanese and I believe that it is still CRIMINALLY underrated.
No, you don’t need to pay. You don’t need to wait either. The defaults are set to anticipate the needs of the average user, but just about everything is customizable. Study what you want, when you want, for free.
You can go to a schedules settings and set up how much you want to learn for the day. And you can go to community lists to add more schedules if you want to try learning other different things in a day. There's probably more but that's usually the most I do.
You can also access all of the lessons at any time, without the daily learning restrictions in your schedule, by going to the menu under Resources → Japanese Lessons.
The only restrictions are, as other people have noted, customizable settings to prevent people from unintentionally studying too much at the beginning, then get hit with a ton of reviews 1-2 weeks in and give up because of the perceived difficulty. It does take some time to look through all the settings, but you can learn at whatever speed works for you.
