I have an app that have hundreds of users and connects to Evernote. As I have more users I make more requests to Evernote and it is causing a lot of rate limiting for my users and causing frustration. Is there a way to get my current limit increased from Evernote?
I have fixed a lot of inefficient calls I used to do, but we still have the same issue.
Rate limits are applied to calls against the Evernote API on a per API key, per user, per time period basis. This means that the API limits the number of calls a third-party app can make for each individual user during a given one-hour period. [source]
The number of users of your application is irrelevant. The source for that quote details a number of reasons and fixes.
If you've optimised your code fully, this may be a "special case". You should contact Evernote developer support.