Hi
Yesterday I noticed that the iPhone app doesn't count down to 0 the review due. Yesterday in my case it went down to 9 and then got stuck there. For a long time.
Today it counted down to 10 (in the normal fashion) and now got stuck there, although I must have reviewed at least an other 25 cards since then. (Yesterday I reviewed way more than 25).
I am wondering if the overall count is incorrect? (But yesterday even after an hour if skrittering I never came down to 0) or is there some other problem?
It's not a huge problem, but it helps motivation to hear the chirp at 0 and it starts adding words automatically while this way I seem to need to add them manually.
Anyone else having this issue?

It sometimes does this for me. It normally hovers somewhere above zero even if I have adding set to manual. I look at the percentage due on words to figure out if they are "below zero" I.e. Less than 100pc due. I use manual adding as I don't like the pop ups when adding. Motivation comes from getting through lists for me rather than clearing the queue, so I monitor my lists pretty closely and follow the progress there and add depending on how far I'm getting through.

It's possible that there are a few words that it can't study due to some sort of incomplete data, so it skips past them. (It should be also removing them from the due counter, but maybe that's not working.)

Is this a new problem, and did you add any words recently that might not be complete in our system?