I'm not sure if it's just me, but for the past 24 hours I haven't been able to sync properly in the iOS app. Unfortunately I'm only using an old iPod touch so my version of Skritter is the old, non-iOS7 one.

It will say "syncing" and then just stay like that for a while, and then eventually just say "Paused - had error". I tried to force sync repeatedly many times but didn't have any luck. I felt like in the past when I have syncing problems then clearing my local data helps so I did that, and now it's really screwed because it can't even finish doing the "Assembling" during the initial sync.

I tried using my VPN and it seemed to have some success, but unfortunately I can only connect with L2TP or PPTP which means I keep getting disconnected from the VPN before it can complete (my Android devices and PC I can connect with OpenVPN so I don't have this problem).

Clearly there is some problem with my Internet connection in China (Beijing). Is anybody else in mainland China having this problem or is it just me?

This happens with both my home and work Internet connections.

Stuart, I also see this from time to time. Last year, I also reloaded all my data on my iPad and I ran into the same problem. Since then, I don't dare to clear my data anymore. I am also on an old iOS version.
I guess, that the web page loading problem and this problem are related. I also see some other minor problems, which indicate unstable connection, e.g. yesterday I reviewed around 3000 items. I found about 5 items came up later the day, although I had studied them before (on the web app), however, Skritter saying something like studied 6 months before.
BTW, this morning all the web pages loaded without any problem, so nice sporadic bug, hard to catch. Might be a mismatch of some timer / watchdog somewhere, web browser, server, app,.... + the slow internet connection in China.

I too have been noticing this problem last few days. Seem's to be getting worse. :-/

Though on a 100M connection, and a good VPN, no problems getting around it.

I also notice without the VPN, various elements of the main site also not loading any more. I'm going to guess various content hosted externally is being blocked and causing scripts to fail since the some pages still work.

I have experienced all those kinds of sync issues as well Roland, for the entire time that I've used the iOS app (more than a year). What's different about the past day or two is that I literally can't sync at all, and especially now that I've cleared my data that means I can't use Skritter at all, which is a rather terrible situation. I always tolerated the sync issues before because with a little bit of patience it would always sync eventually, but the way things are now I'm just screwed.

hessinger, do you use a VPN on an iOS device? If so would you mind letting me know which one it is and how you connect?

Stuart, I did a sync this morning on my iPhone, where I didn't use Skritter recently. I only had about 2200 items to sync, but it took about half an hour before it was successful. Now, you have more than 30.000 ....
I also use VPN sometimes, ExpressVPN, on Windows / Mac / iOS. It normally works quite OK, but is not the cheapest one.
I'm right now on VPN for the web app, because it had server response times before of up to 60 sec.

Right, I have over 30,000 items to sync and it always fails with a "Paused - had error" message, and when I try to sync again it doesn't continue from the point it stopped, it has to start the whole process again.

Would you say connecting to ExpressVPN in iOS is reliable? Do you ever have trouble connecting, or do you ever lose the connection?

I only lost connection, when it was idle for some time. I experienced sometimes problems, when connecting. I believe, then the Great Firewall was blocking connnections, normally it took the guys a day or so to come back. But this was not very often.

After trying all day, I've finally managed to get it to sync completely. I don't know if it's because something got fixed somewhere or I just got lucky, but I will definitely be afraid to clear the local data again.

Working for me as usual, in Shanghai, without VPN.

It's working alright today for me as well (so far). Keeping my fingers crossed it stays that way.