GPS need to log and link to up to 24 individual satellites. From startup it can takes several minutes to get accurate results, especially the older ones of few years ago. My Canon GPS will/ must be switch on a minimum of 5 minutes to get a reliable reading (with altitudes out more or less 5 m. - which is impressive). Nowadays the newer GPS relies on the Russians to improve the GPS accuracy (GLONASS).
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OK: so you are talking the “Os Grid References” - I dont think the rest of the world uses them, and if you have coordinates, why do you need to worry about them at all?
Or do you fill in the Os Grid References and the latitude and longitude fill in from these automatically?
I see that the instructions on the ADD an OBSERVATION page say that one has to press a GO button, but I cannot find it. (added as bug #480 - although perhaps it is not a bug, just an unproofed page with faulty instructions …
On the older version you had to press the GO button when entering a location by some means (include the OS grid reference). It was failure to do this that resulted in the trickle of observations mapped to Luce Bay off the Scottish coast. That’s no longer necessary, so this looks like a failure to update the instructions. Faulty user instructions still qualify as bugs.
GPS is amazingly accurate, although as you say, 5m accuracy horizontal is usually attainable, but 50m error vertical is often exceeded.
I must confess to me mostly impressed though with the accuracy. What was fun was walking in the river gorge below Macho Pizza (sorry Machu Picchu) and with so little sky visible the GPS went haywire - none of those localities was remotely usable: up to 5km out. But that is to be expected. One also has to double check observations from around Table Mountain - not only the gorges but also anywhere too close to cliffs - not only is half the sky missing, but there is also echo off the cliffs which confuses the GPS, but again modern GPS clearly anticipates some of these problems.
I have probably told you this already many times. But on a Protea Atlas Project trip in 1994 we tested the latest GPS up Touwsberg. It weighed a kilogram, had an aerial 200mm across, took two readings, taking 5 minutes per reading and was accurate to about 100m and the battery went flat. And we climbed 800m for that. Needless to say, for the rest of the Protea Atlas Project (until 2002) we used ordinance survey maps.
But the PAP encompassed 1990-2002 and during that time we saw PCs became important (vs mainframes), we changed from paper cards to stiffies for storing date, emails arrived, the www arrived, and GPS arrived. Had we started the PAP at its end, it would have been an unrecognisable citizen science initiative.
Some other countries (e.g. Ireland, including Northern Ireland) have their own grid systems.
In Britain detailed mapping and biological recording is based around grid references rather than (spherical) coordinates.
The program I use to access GPS logs only allows one representation at a time, and I want the GRs for entering into my own files, or for reporting to vice county reporters. In principle I could switch between formats, and use spherical coordinates for entry into iSpot.