WAAS GPS vario?

Is anyone working on or studying using WAAS GPS data to make a stand-
alone vario? How would TE be implemented in such a device? Ground
speed change during a pullup? TAS based on circling winds?

Do the current PDA software programs (mSeeYou, Winpilot, etc.) when
used in GPS-only mode provide accurate vario data when hooked up to a
WAAS GPS?

Just curious - seems a 5 hz WAAS GPS could be the basis for a really
nice vario that wouldn't need any pitot-static imputs. I use mSeeYou
and a Themi, non-WAAS, and the "vario" data seems close, but I use it
more for trend and average than instantaneous data.

Winter can't end soon enough!

Kirk
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