The wifi is either going to host a connection to your tablet or be a host to the marina/boat wifi to get weather and use the cloud to sync points etc. (not both) If you take one MFD and connect to the internet it can feed the weather and cloud. The other units could be setup to host any tablets for running "NavNet remote" or any other of the many established apps. What you never want to do is leave a unit setup looking for internet connections and not connect to one of them. That constant searching will eat a ton of CPU time and will affect your unit operations. Connect OR, turn it OFF wifi, OR host a connection to tablets.