We presently use cellular internet on the boat. When we first added the boat Hotspot to our so-called "unlimited" Verizon account for a mere $10 a month, we quickly found out that for a hotspot, the data is throttled back to an unusable speed after 15 GB of use in a month. Working from computers, streaming films to our TV, etc. can use this amount of data in a day. So we then got a SIM card with really unlimited unthrottled data. It is more expensive but great to use when we are staying on the boat. But it is somewhat wasted when it is docked for long periods (Although I do use the boat as a man-cave office when it is docked here near our home). Really high speed satellite data service requires the large domes you see on mega yachts, and is super expensive.
So I have followed with great interest the development of the Starlink internet service by SpaceX, Elon Musk's plan to launch eventually 42,000 small satellites by 2027. Anyone who has been traveling up or down the east coast of Florida has noted regular launches of rockets from Cape Canaveral carrying 60 satellites up at a time to place into orbit. It is fascinating that the rockets are reusable and land on drone ships when they return to earth. One of these robotic ships is called "Just Read the Instructions" and another is called "Of Course I still Love You". The names were originally used for spaceships in books by sci-fi author Iain M. Banks.
Currently there are around 1,000 satellites in operation and Starlink is offering "Better Than Nothing Beta" service to a limited number of users in some parts of the world, including most of the United States. A kit includes a small dish to be mounted outdoors clear of obstacles, a modem and WiFi router for the house, and a 100-foot cord to connect the two. The cost is around $500 for the kit and $100 a month for internet service. SpaceX said last October that users should expect speeds between 50 and 150 Mbps, with intermittent outages. Some users are getting much higher speeds -- the highest download speed to date was 209.17 Mbps, recorded in New York and one person in Utah recorded a speed test showing 215 Mbps.
So can it work on a boat? The answer for now seems to be no, unless the boat never moves. While the dish will automatically track the overhead satellites, it will not accommodate rocking and rolling on a boat. Some users have had luck with a gyroscopic mount or with the type of gimbal mount used for radar on sailboats, but there are some reports of the system shutting down when it senses motion and requiring a reboot. It is all basically experimental for now. More importantly, the system only broadcasts to the service address you give when ordering the system. As the Starlink website states:
Starlink satellites are scheduled to send internet down to all users within a designated area on the ground. This designated area is referred to as a cell.
Your Starlink is assigned to a single cell. If you move your Starlink outside of its assigned cell, a satellite will not be scheduled to serve your Starlink and you will not receive internet. This is constrained by geometry and is not arbitrary geofencing.
Starlink has said that they are working on "mobility solutions" that might be accomplished in the future by a software update to the satellites. But at least for now, I don't see any way to use the service on a boat or motor home, or to otherwise move it from place to place. I'm hoping one day it will be useful for people on the go.