What is your preferred fitness tracker/smartwatch?

I'm an avid paddler/wind sports/surfer, so having good water resistance, cellular connection for emergencies, at least 4+ hours of GPS tracking battery life, and good GPS are requirements. AFAIK only the Apple Watch Ultra ticks all those boxes. I used to use Garmin's but the lack of cellular made me switch. If anyone has other options, I'm open to them.