Magic Jack while in US

I'm not sure I understand where the tracphone comes in. Although I live in the US, I do use the mj to make calls to Canada without any problems. If where you snowbird you have cable, just plug the mj into the modem or router using the Ethernet cable. You can then attach any regular phone into it. I use a cordless phone but any phone should work. Also if you have a smart phone mj has an android app for it so its not using minutes or applying out of country charges. MJ, best thing since sliced bread and only $20 a year.

I have had zero luck in using a MJ over any WiFi connection whether it was the 4G LTE that I used to have with Millenicom or any park WiFi even when the park WiFi was fast. It worked when on the Frontier land line DSL connection but has never worked on WiFi. I gave up on MJ while traveling and bought the Straight Talk home phone system. $15/month plus tax and I think the hardware was $90. It operates on the Verizon network and I just let it expire when I get back home. The only problem is that it will reassign a different number when it is reactivated when I go south for the winter.

For consistent quality VoIP, you generally need to be connected to a wired broadband connection. Using any type of mobile data 4G/3G will be a hit or miss proposition.

Though VoIP doesn't require much bandwidth, it does need a quality, consistent connection.

Mobile data tends to suffer from higher latency, or jitter which can cause interrupted or distorted conversations. Though MagicJack uses a high quality voice codec, it doesn't allow the user to configure custom VoIP settings. It's a set it, and forget appliance for simplicity sake.

You may be better off using a VoIP service such as CallCentric, and buy your own VoIP device that allows you to choose supported voice codecs, and set other custom settings. May offer better quality than using MJ, but setup can be intimidating if you haven't done so previously. Basically, if you've setup(admin) a router at some time, you shouldn't have too much difficulty.

BTW, there are some advantages of using a VoIP service. Such as setting your own caller ID phone number for outgoing calls. For instance, I have my CallCentric VoIP number set to display my Google Voice number when making calls. Not the phone number I was assigned, which I couldn't recall if ever asked. I'd have to look it up.

Still, I wouldn't expect to get the same VoIP call quality from mobile data, as I would from a wired broadband connection.

We use Magic jack as our home phone number in Canada. We have a Rogers rocket 4G data hub supplying our internet access and it works just fine. We use the MJ Plus where we don't have to have it connected to a computer and hook it directly to the Rocket Hub. When we travel south for the winter we use to take the MJ Plus and use it from our lap top when we connected to WiFi (ie) Mc Donalds, Lowes, Campsite's etc. We now just use the App on my wife's Ipad to call and answer our phone anywhere we have WiFi access. We can now leave the MJ at home for 911 calls if our house (babysitters)need it. The trick is to have a designated MJ phone number ($10.00)/yr extra and register the number on the Apple app when installing it. This seems to eliminate most of the MJ issues re lag time delays and call dropping. This way we take our home number with us where ever we are and don't miss any calls. MJ also emails our voice messages, so if the WiFi is poor we can still check our messages to see who called and why. Family can get us anywhere and it's just a local call for them, no long distance charges.
Like most other snowbirds we also carry a cell phone for on road emergency use. We have an unlocked phone and use a pay as you go Global travel G3 wireless simm card (no roaming fees) It's only 9 cents a minute local/long distance and data is only 9 cents/MB anywhere in US. In Canada it's 25 cents/minute. So if there is no wifi available I take the Simm card out of the phone and put it in the Ipad so my wife can check emails and make lenthy MJ calls to our daughters from her Ipad App. We find that the MB usage for making MJ calls on the Ipad is on average 1-2 cents per minute.

Hope I wasn't to long winded, getting eager to head south.