You can change this any time in Settings, under Players.
Open Water is best on a computer or tablet, since a phone screen is a bit small for it.
The boat cruises until you take the wheel: W or ↑ to speed up, A D or ← → to turn, S or ↓ to slow down and back off. On a tablet, drag on the sea: up to go, down to back off.The boat cruises until you take the wheel. Put your thumb anywhere on the sea and drag: up to go, down to back off, sideways to turn.
