Thought I would share my experience of this situation: My company makes an app for iPad (Report Monster) which can send photo-based pdf/kmz reports to Evernote. Our files can be anywhere up to 6MB each. Until early November our Evernote export function worked flawlessly - we could export multiple large files all day long without any issues. After the Evernote 'upgrade' in November, our app became unable to upload large files to the Evernote server on a consistent basis. We even saw files as small as 100kB fail on a regular basis! The problem seems very inconsistent and sometimes a full 6MB file uploads without any issue. To cut a long story short, we have been communicating with Evernote for the past 6 weeks and have tried changing connection time-out periods, and even implemented a new custom SDK supplied by Evernote. Nothing has worked so far. Our export via Dropbox and Email still works flawlessly, and we made no code changes around the time when the problem began. I hope slowly Evernote will realise that this is a server side issue, and not a client side issue.