gps-speedsurfing

`i am havinhg difficulties understanding what `gps units are `ratifiable , I have been using a GT31 ane its just about had its time now, is the new ````Apple watch Ratifiable? as say as aqurate as a GT31 and can it be used fior rankings, Had a Coros Apex pro but the strap snapped only a few months old so relucdtant to go down tat route again.

 

Thanks in advance.

Richard Hobson.

SEVERNE