I was not aware of the TNC from Mobilinkd, so thanks for the tip. Interesting that their newest version includes BT connectivity to a smartphone app - something that almost every op has handy when making "portable" sat QSOs. It's compatible with APRSdroid and they are working on adding iOS. A prescribed format APRS message app, running on a smartphone, would be an interesting alternative to the raspberry pi route. The TNC's small form factor would make it more usable. $120 is a reasonable solution for those who do not want to build one. For the more adventurous types, building one looks like only $20-$30 worth of parts. NOTE: I own APRS capable HTs and Mobiles and have made APRS QSOs; however, I am exploring ways to make APRS messaging more accessible and more enjoyable for everyone. I think automating/symplifying the QSO process, with a low-cost add on to existing equipment, could do that. Robert KE4AL