MiFi devices that I've purchased in the US have always supported at least 5 simultaneously connected devices. The one I bought in Italy
a couple of years ago, only supported 2, even though it was supposedly the same brand & model number as the ones that I had previously purchased in the US.
I haven't used a MiFi in over a year now, since my Andriod will do double duty as both a phone
& a hot spot. If you shop around, you can get unlimited voice & data for as little as $40/month in South Florida
All of these devices are limited to cell phone
range from shore. These days, I find that to be around 8-12 miles max in most places for a 3g or 4g signal. If you have a phone that supports the older analog cell system, that number stretches out to around 30 miles in some places.