IFR with a VFR GPS

Recall that the NTSB accident database has at least one recent C172 fatal
accident where the NTSB concluded that the pilot was flying a GPS approach
with nothing but a VFR GPS.

What was the cause of that crash? Was the VFR GPS giving erronious
information? Was it hard to use, not being attached to the plane? Was
the pilot unfamiliar with the device? Was the approach even in the
database?

Jose
--
He who laughs, lasts.
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