getSettings
Must be implemented by the application to specify its preferences/settings for NFC engagement.
Note that this is called after the NFC tap has been detected but before any messages are sent. As such it's of paramount importance that this completes quickly because the NFC tag reader only stays in the field for so long. Every millisecond literally counts and it's very likely the application is cold- starting so be mindful of doing expensive initializations here.
Return
a Settings object.