It looks like Gmail is not working for some iOS device users.
According to this forum thread, users seem to be getting the ”mail service imap.gmail.com is not responding” error, when trying to fetch new mail from their iPhone, iPad or iPod touch.
AllThingsD reports that Google has acknowledged the issue and is working on the fix:
We’re aware of a problem where Apple Mail IMAP users are unable to sync with their Gmail account and are seeing a username and password error. We have found that a vast majority of users are exceeding IMAP bandwidth limits and are continuing to investigate.
It’s quite weird that the issue is only affecting Apple users.
If you’re facing the problem then use mobile Safari on your iPhone, iPad or iPod touch to access your email as a temporary workaround.
We’ll let you know when the issue is resolved.