Application Loader Warning - Resulting API Analysis File is too large
Solution 1:
As it mentions already, it's just an informational message. You don't need to worry about rejection because of this.
What it means is that it cannot do API analysis before upload. It does this analysis to check if you use any restricted API's from the SDK. So it could warn you and allow you to fix it before uploading. Since it's too large, you will get the warnings (if any) about API usage by email within half an hour or so after submission since the analysis will be done on the Apple servers.
Solution 2:
It's nothing to worry about - Basically, when you archive your app it produces an "API Analysis File" which is a breakdown of every call your app makes to any of Apple's frameworks. This allows them to see which services you're using, and if you're using any private APIs that are considered off-limits. If your app is big enough (which doesn't take much), this file gets "too large" to send to Apple. So instead, they just run same analysis on their servers after the upload finishes.