Your phone probably supports FHSS WiFi on two bands - 2.4 and 5.8. For each, it's only connecting to one or the other, and is thus single band FHSS once running, but it has two bands available to it. If one is overloaded (usually 2.4) then you can tell it to move to 5.8, but it's usually a manually-selected thing (though it can be automatic).
The truth is, there are advantages to both. The best solution would be multiple bands, frequency hopping within each. That is, technically, just a matter of expanding the spectrum of allowed frequencies.
Since you're talking boats, you especially need to understand the problems of operating 2.4gHz over water and how greatly it diminishes range. It is far from the best band to use. Right there your competitor has a huge advantage because 433 & 868MHz are going to have much better performance over the water, but you being on 433 isn't an issue.
Andy