Suggestion: Daily short certificate tests
I was thinking about practicing really hard every day and taking the certificate exam every day. The thing is, I realized that the certificate tests are pretty long and expensive (If you were to do it every day).
I was wondering if there could be something similar in the store, like mini certificate tests which you could do every day, (which of course would be cheaper 5/10 lingots etc.) or every few days/week. I was wondering if this idea might be a little bit similar to the coach feature. If it is, I hope the Duolingo team plans on adding the feature to the web version.
I've only done a certificate test once, but it seems to be just untimed practice with a finished tree, without peeking. You can always do that and keep track of how well you are doing (number of hearts left), simultaneously strengthening your weakest words.