In the V1 iOS SDK it was possible to logout the current user as follows:
[Box logoutWithCallbacks:^(id <BoxOperationCallbacks> on)
Here's what I do:
BoxSDK *sdk = ... // a reference to the BoxSDK for the user sdk.OAuth2Session.accessToken = @"INVALID_TOKEN"; sdk.OAuth2Session.refreshToken = @"INVALID_TOKEN";
That's it. The next time you try to do anything with the user's session you will be forced to log in again.
Update - you can see this in action in the Box sample app at https://github.com/box/box-ios-sdk-sample-app. Look at the