Reviewed Jan 2017
Have Boat Book Sailing Log loaded on my Android. Quite forgot it was there until it started logging sea cruising/racing. Seems that it recognises when you "hit the briny" and then sends you a message when you complete your voyage and another when you go ashore. Very clever. Then you can view or forward your voyage track and the distance travelled, oh and GPS co-ordinates. You can also record "events" along the track.
No speed, ave speed or other data as yet but If they've conquered this so far the rest will follow closely I reckon.