Does phone GPS measure a disc throw well enough to build on? Throw ~20 times and find out.
Live GPS fix
—m accuracy (±)
Tap Start GPS to begin.
Mark mode — the A/B test
Hold still…
Alternate between modes as you throw. If Precise doesn't beat Instant on your courses, it isn't worth the wait.
Last throw
—
Session log — 0 throws
#
Mode
Feet
±ft
Err%
Δalt
How to read this
Error % is the combined ± of both marks divided by the measured distance — how much of the
number is noise. Under ~10% the measurement is trustworthy. Over ~25% you're mostly measuring GPS error.
Throw a mix: drives, approaches, and a few short ones. The short throws are where this is
expected to fall apart — confirming that is part of the test. Walk to the disc and stand over it before
marking landing.
Δalt is elevation change from GPS. It is far less accurate than horizontal position — treat
it as a rough hint about uphill/downhill holes, not a measurement.