19.7: Added option to follow route in
reverse on Goto page. Compass page can now show magnetic or true
north, plus optionally pitch and roll. Added option to beep when
GPS fix lost. Fixed a further bug reading KML files.
19.6: Fixed bug with importing some KML
files. Changed "Delete all" option to be "Delete all and reset".
Added a "copy" button to allow copying grid refs to
clipboard.