This is a bit of a strange request, however I need to borrow an accurate GPS for a day to survey my property boundary. Sadly I don't think my iPhone GPS is accurate enough for the job as the coordinates jump around too much and it really needs to be accurate to within 20cm. Preferred accuracy would be to 2 decimal places of a second. I would be exceptionally grateful as I'd prefer to avoid buying a GPS if I can as my iPhone is normally good enough for most uses, particularly with Memory Maps loaded onto it.
Thanks in advance for reading my request,
Cheers