Iím not sure how the GTX345 fits into this. I know you can Bluetooth to the 345, but not sure if the Bluetooth to the GTN gives you the data it gets from the 345 or not. I think it does from what I have read, but I donít know from experience.
As of the most recent firmware udpates for both the 650/750 and the Flightstream 510, data from the 345 now passes through the 650/750 via the FS510 into Foreflight. This didn't work until the last round of updates.
With a single bluetooth connection between the FS510 and Foreflight you get GPS position, bi-directional flight plan transfers, adsb traffic & weather and attitude/heading/etc. from the 345's built-in AHRS.
The 650/750 software can be downloaded from Garmin (via the G3x page) for experimentals, but unfortunately you need to use the Garmin Pilot app *in a dealer account* to update the firmware on the FS510.