One thing that you'll notice when you start cruising is that most cruisers are addicted to the internet. Less so than our land loving brethren, but addicted none the less. Sure we go weeks without internet, but when cruisers are at anchor we stay in the places where there is wifi. You'll visit all kinds of nice anchorages. Many won't have any sort of internet, or cell service, or anything. But most boats stay longer in the anchorages that have wifi. And many of these anchorages have less shelter, are more crowded, and are generally less comfortable than neighbouring anchorages without wifi.
We did this for a couple years, but we have recently managed to break free thanks to the following device.
It connects to the cell phone network. It gives us broadband speed for at least a half dozen miles from the nearest cell tower. This lets us anchor pretty much anywhere in the popular cruising areas of New Zealand and stay connected.
The power consumption is much less than an amp at 12 volts and it can be charged through a cigarette lighter adaptor.
It's not cheap. The router itself was NZ$300, and it costs us NZ$80 per month. But when you consider that we were staying in a marina when we bought it at least partially for the internet, it doesn't take long to pay for itself.
We bought an expensive wifi antenna for the boat before we left Canada. It has never given us a connection over half a mile away, despite the promises of a much longer range. I recommend a cell phone network router, like the one we have, rather than a fancy wifi antenna.