You can send Flash messages directly from your Call log, T9-search and from Contact tab. Search name or number > tap on the 'Thunderbolt' icon.
Please note that "Availability" (last seen) feature must be enabled in order for it to work.
How to turn Availability on:
iPhone: Open App > More > Settings > Availability.
Android: Open App > Menu > Settings > General.
For more questions, please contact our support.