I recently reinstated my subscription after getting an iOS device and am having trouble figuring out what exactly is going wrong with regard to the disparity between my due count on the site and my iPad.

I've gone through hundreds of reviews today on the iPad, and from checking the sync history it seems like everything is syncing fine with the correct numbers, yet the due count on the site doesn't change at all, and continues to say 0 on the iPad, (though it is giving me the same small set of vocabulary to do over and over).

When doing some reviews on the site I can see they have synced down to the iPad as well, but the words due on the site are completely different than what the iPad wants me to do. No matter how many reviews I do it keeps giving me the same stuff over and over rather than letting me do the due reviews from the site.

I've edited word lists on the site and had them all sync fine to the iPad as well, so I really can't figure out what's going wrong here. Please help!

(Update)
I just tried downloading the Android version for my old Nexus tablet and it shows the same due count as the site. Unfortunately the actual writing seems quite laggy when compared to the iPad Air 2. The fact the Android version corresponds to the site and the iOS version doesn't just puzzles me further, however. I'll try a full re-install of the iOS version and report back.

(Update 2)
OK, that seems to have fixed the issue. The strange thing is that I'm certain the width of the brush strokes have shrunk after re-installing the app... I actually prefer them like this, but I've no idea why such a thing would occur. It still seems quite temperamental about when it will and will not register me pressing the side to skip to the next kanji, though!

I have the same problem on my iPad (chinese app). I reinstalled many times but it's always the same problem. If I use the website or my iPhone the reviews are normal, but it doesn't work with my iPad.

@Tuoma31

The only thing I did differently was download the app directly from the iPad itself, rather than through iTunes. I don't think that makes any difference, but thought it might be worth mentioning just in case.

I find that iOS slowly goes out of sync over time. It usually doesn't bother me though as I never use the web for studying, although occasionally I have a strong feeling that it has forgotten words that are due. But normally about once or twice a week the Skritter app either crashes or (more frequently) gets evicted from memory when I use other apps, and when Skritter starts up again it's back in sync. Occasionally I just kill Skritter and restart it if I believe it's too out of sync.

In my case I've noticed that the iOS app gets heavily (and constantly) out of sync if I select just few lists (advanced study) no matter if I later force close the app or I change device ( from iPhone to iPad).
Usually after 2/3 days everything is back in sync, but as soon as I pick advanced studies again the problem reappears!