IOS 10 issue: fails to connect to server

Meteor version 1.4.2.3
IOS: 10.1.1
When running / building the app, the app refuses to connect to backend. Not getting any access allow errors, just time out (although connection is no issue). Just browsing to the app in the device browser it works fine. The cordova app not.
Not getting any error, neither in console n’or in xcode. CSP seems fine too.
Tried & checked all CSP solutions.
Any suggestions?