Managing Active Sessions
Single Sign On
If you're playing RuneScape on Mobile your login details will be remembered on your device!
To remove Single Sign On tap "Sign out". Next time you login you'll be asked for your Username and Password (and Authenticator code, if you have it set).
Manage Active Sessions
Alternatively, you can cancel all active sessions via your Active Sessions settings by hitting "End Mobile Sessions".
This means that any stored SSO tokens will be removed. Additionally, changing your Password in any way will result in the SSO token being removed.