3- Enable the LimeSurvey JSON RPC API
Offline Surveys requires the LimeSurvey JSON RPC API to be activated at LimeSurvey in order to be able to connect to your LimeSurvey system. You can activate the API at LimeSurvey at:
Global settings -> Interfaces -> RPC interface enabled = "JSON-RPC".
Note that if you are not able to access the Global settings menu at LimeSurvey, this may be related to insufficient user rights. In this case please get in touch with your system administrator / IT department / provider and ask them to enable the API for you.
Make sure that the URL shown at the LimeSurvey interface settings (see screenshot below) is the exact same URL as entered at the Offline Surveys app.