Expand allows you to return additional fields that are not included in the default fields (comma-separated list).
Supported fields:
app_last_login_ts: Timestamp of last login via the mobile app
created_ts: User creation timestamp
invite_created_ts: Timestamp when the invite was created
invite_sent: Invite status (0=unsent, 1=sent, 2=accepted, 3=expired, -1=failed). Null if the user has no invite
last_login_ts: Timestamp of last web login (mobile app logins are tracked in app_last_login_ts)
modified_ts: Last modification timestamp