Our parent application handles the user login, however we are wondering how we should transfer this data over to the WatchKit extension. To clarify, we have a REST API which serves as a primary interface to retrieve all the user data, however to access this API we requires to use an access token. The problem is, how should the WatchKit retrieve this token which should be kept secret (which is acquired at user authentication in the parent app. and saved in the Key Chain). I assume that any method using the Bluetooth/wi-fi to transfer data (such as openParentApplication:Reply method) would be unsafe as anyone with a packet tracer could easily see the data.
Keychain sharing seem like it would not work as I assume in WatchOS2 the iOS and WatchOS file system are seperate.