I have a mobile app (iPhone/iPad) for recording data and taking notes, including photographs, and a government client needs GPS coordinates attached to each photo.
They require coordinates in the GDA94 and/or MGA94 specification, but I can't find any concrete instructions how to convert from a standard lat/lon into those two — and sadly many of the references I did find are out of date or refer to 404 pages.
Is there a simple way to do the conversion? It doesn't need to be accurate since I'm just using a smartphone GPS chipset. But I'd like something with better than 1m accuracy.
As far as I can tell, WGS84 and GDA94 were identical in 1994 but due to continental drift are around 1.4 metres apart now (iOS GPS coordinates are in WGS84 aren't they? I couldn't find any definitive documentation for that either).