I could not find any documentation of the process that leads to a message being displayed on the mobile app. For instance, we sent a message from Moodle with the following text component (the "fullmessage" property):
The HTML part of the message seems to be ignored. When the mobile app displays the message, the last URL of this text is converted to a link, but the former URL isn't. What are the rules?
See the forum for a few unanswered questions and reversed engineered suppositions.