I learned today that the SOTA folks have a system that leverages APRS for spotting:
Does anything similar exist for WWFF?
I, for one, would be interested in such a system. I often find myself with a drained phone battery and a noticeable hit to my data usage when trying to activate a park. Or in a park where there's little or no cell service. I have some spare tablets that have wifi, but no data plan. I've been thinking about setting up a Raspberry Pi + Direwolf + WiFi + radio, and having APRSDriod on the tablet using Direwolf (across wifi) as a TNC. But I know of no way, currently, to send a message through the APRS network and have it converted to a WWFF spot.
Of course the reverse direction would be equally useful: receiving spot data from other activators via APRS message, for those P2P contacts.