The same problem here when following the http://docs.moodle.org/dev/Moodle_Mobile_Developing_a_plugin_tutorial
Mi moodle versión is 2.6.2+ with the Moodle Mobile 1.4.2
The test with the client works OK (/local/custommm/client/client.php)
I can login the app, I open a course and I click "Grades". All the activities are loaded but when I click one I get the message:
we lost connection, you need to reconnect. Your token is now invalid.
and after two seconds it goes to a black page with a pop-up:
Uncaught TypeError: Cannot read property 'id' of null