text: Notes are not intended for place markers. You can use the share button with "show markers" but I'm not aware of a way of showing a GB grid ref apart from this site (http://www.cucaera.co.uk/grp/?refs=TQ432149&map=ordnance_current&vcs=true&graticule=true&nsgrids=false&zoom=16&lat=50.916376568937935&lon=0.03566759623068627) which (incidentally) suggests you either have location of grid ref wrong.