Wifi is pretty limited in the exumas. Witht he Rogue booster I usually get a good free hotspot on the east side of th normans cay anchorage (east of the dc3) but not further west near the dock.
Warderick wells has limited and expensive service that you ha to prepay at the office.
Around Staniel, Exuma wifi seems to have reduced their coverage. Staniel has wifi at the dock, but limited bandwith.
Nothing further south till you get to Gtown
We ve been using BTC. While most phones are locked preventing you from using in a BTC sim, tablets including iPads are not so now the best solution is to buy BTC sims and putting them in. As Dan mentioned it s $30 for 2 gig which is pretty reasonable. The problem is that you need a BTC to phone to activate the data plan. It s a bit of pita every time you need to put other 2 gig to take the sim out of the ipad, putting it in the BTC ohone, do the *205# thing to activate a new plan, shut down the phone, restart it and then out the sim back in the iPad.
I also have a basic BTC droid Galaxy which I use to activate the dataplans. It can also be used as hot spot so various users can share the connection. One thing to keep in mind though is that most new devices like iPhones, iPads and I imagine others, will do a lot of backing up and background stuff when on wifi whereas the same ipad with using cel data with its sim will not, making your plan last longer.
Reception is good around highborne and normans, weak as you move south to shroud and hawksbill. There is pretty much no cel reception in warderick and it picks up again around Cambridge and pipe approaching the tower at Staniel.
Service around Staniel is slow because of the amount of people using the tower.
It's very good around blackooint and little farmer, dropping again once you reach Rudder and picking up again at Lea stocking and Barraterre. Having spent most the last 3 months going up and down between nassau and Gtown, I know pretty well where it works
One more thing... In addition to setting up an online account on the BTC website so you can refill the account by credit card when using a BTC sim in an iPad or other device you need to go to settigns>cellular data>APN setting and put in internet.btcbahamas.com in the APN field.
Finally , if you are an ATT customer you can sign up for one of their new passport plans. They are good for 30 days and vary between $30 and $120 giving you cheaper roaming and messaging than BTC. Deoending on the plan you get as much as 800MB of data. I used the $120 plan and was paying 0.35 a minute for voice which is pretty good.