Piggybacks on: T-Mobile
Starts at: $19 per month for unlimited voice minutes/texts, 100MB data
In business since: 2014
Along with H2O Wireless, Ultra Mobile is among the few carriers to bundle international calling and texting along with the usual menu of services. The $19 starter plan includes unlimited calling within the U.S. and to 11 countries, unlimited global texting and $1.25 of "call anywhere" credit, while the $29 plan adds 1,000 international minutes (which are good for calls to more than 70 countries).
Ultra Mobile doesn't sell phones, and its website could do a better job explaining the company's BYOD options. Basically, you pick the plan you want and then order a SIM card for your unlocked GSM phone. The card is included with your order, which covers your first month of airtime. One important fine-print detail: If you choose the $19 or $29 plan, you don't get unlimited data: Mobile data is turned off once you exceed your allotment, leaving you no option but to buy more or wait until next month. Higher-priced plans include unlimited data, but as with most carriers, it gets throttled to 2G speed.
Piggybacks on: Sprint
Starts at: $35 per month for unlimited voice minutes/texts, 1GB data
In business since: 2001
Not long ago, Virgin Mobile offered some of the most competitive service plans around -- provided you were willing to buy one of their phones. The company continues to offer a good mix of models (including the iPhone 6S), but you still can't bring your own, and the carrier's service offerings now seem merely average, not exceptional.
However, if you like music, there's a solid perk in the form of Virgin's DataFreeMusic feature, which lets you stream unlimited tunes from the likes of iHeartRadio, Pandora and Slacker without impacting your monthly data allotment. Just make sure to check the coverage map first: Although Virgin taps Sprint's network, it doesn't provide the same roaming blanket as Sprint proper -- a potential problem if you live, work and/or travel in remote areas.
What the heck is Project Fi?
You've heard of hi-fi and Wi-Fi, but Project Fi? That's what Google is calling its entry into the carrier space, though don't expect the Big Four to become the Big Five. Instead, Project Fi will utilize both Sprint's and T-Mobile's networks, with a special SIM card toggling your phone between them on the fly.
Why two networks? Simple: Two are better than one. Google aims to provide unparalleled coverage by tapping whichever carrier has the strongest signal wherever you happen to be. Meanwhile, Project Fi phones will take a page from Republic Wireless and TextNow by leveraging Wi-Fi networks whenever possible. And not just any Wi-Fi networks, only those Google has verified as "fast and reliable," the idea being to deliver better-than-average voice-over-IP call quality.
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