I know a lot about cell phones -- part of my day job
What was said about MVNOs is right on the mark... They are basically smaller companies who wholesale access from the major carriers and provide their own data service and customer support... The easiest analogy is the local ISP - - you can still buy DSL from a local ISP, but the actual phone line is provided by the phone company, but the ISP provides their own servers to get you online, and when you need support you call them and not the phone company... EarthLink actually does the same thing with cable. My Internet comes in on a Comcast line but I have an EarthLink email, my DNS servers are from EarthLink, and I call EarthLink for support - - I also save about 20 a month because I have DirecTV for TV... EarthLink doesn't care if I have TV or not... Comcast charges a 'no TV fee' if I get my Internet direct from them. It's the same service.
As for Geoverify... It doesn't use much data at all... So you don't need a huge plan.
So three MVNOs I would recommend in your case:
1. Google Fi: If you like Android phones and van get your hands on a Nexus phone (doesn't have to be the newest... Any nexus phone up to 3 generations back will work), this is the absolute best for low data use. It's a flat 20 bucks a month for voice and text and 10 bucks per gig - - but you only pay for what you use. So if you use 100 megs, your data bill is $1 and the total is $21. They also do something absolutely no one else has done: they cut deals with T-Mobile, Sprint and US Cellular -- and your phone picks the tower with the best signal out of the 3 wherever you are.. It's like having 3 carriers in 1. It's seamless and you just notice you have more bars in more places.
2. MintSIM - - this is a sub brand of Ultra Mobile (also a good choice) except you can buy service in 3, 6 or 12 month chunks... And it's cheap... Right now the 3 month plan is half price... So like 18 a month for a gig of data. They seem to be a little cheaper than Ultra because you can buy in bulk and save. This runs in T-Mobile... Any T-Mobile phone, unlocked iPhone, and many unlocked Androids as well as all Nexus devices except for the AT&T Nexus 6 can run on it.
3. FreedomPop - - they have a 'free' plan with a limited number of minutes and 500 megs of data... This is rock bottom cheap (free)... But the downside with the free plan is it routes calls over VoIP and they aren't as clear... You can get an unlimited calling plan, a gig of data, and their "premium voice" which routes the calls over the regular voice network for like $18 a month. They use the Sprint network... Any Sprint phone, unlocked Sprint or Verizon compatible iPhone, or unlocked nexus phone can use it....
Hope that helps!
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