T-Mobile's new WiFi base station is free with a $25 refundable deposit... and they're also allowing people to trade-in and upgrade to a new WiFi capable phone via JUMP.
"As part of the campaign, it will allow members who don't own a Wi-Fi calling-capable phone who are on the carrier's Jump upgrade program to immediately get a device, regardless of when they were supposed their upgrade. Customers who sign up for the Jump program can also immediately upgrade to a Wi-Fi calling-capable phone."
»
www.cnet.com/news/t-mobi ··· calling/Since it's WiFi, there's no caps or usage limits.
vs.
Verizon: Charges $249.99 for a Network Extender (»
www.verizonwireless.com/ ··· cs-2u01/) which only supports 3G voice/data. Although you can use an LTE phone on it in 3G mode, it won't support VoLTE/WiFi calling. The big problem is that it doesn't boost your LTE coverage. Since it doesn't do WiFi, you need a separate router. Voice/Data usage counts against your plan.
AT&T: Charges $200.00 for its Microcell (»
www.att.com/standalone/3 ··· crocell/ and »
geekbeat.tv/review-att-3 ··· crocell/) which also only supports 3G voice/data. And like Verizon's you can use an LTE phone on it in 3G mode, but it won't support VoLTE/WiFi calling. As above, it doesn't boost your LTE coverage. Since it doesn't do WiFi, you need a separate router. Voice/Data usage counts against your plan.
Sprint: Charges $99.99 for its Airave unit (»
shop.sprint.com/mysprint ··· 77200131), which also only supports 3G voice/data. Although you can use an LTE phone on it in 3G mode, it won't support VoLTE/WiFi calling. As above, it doesn't boost your LTE coverage. Since it doesn't do WiFi, you need a separate router. Voice/Data usage counts against your plan.
This is good for all of us... whether you're a T-Mobile customer or not.
EDITED TO ADD (9/12/2014): Per another DSLR user, Sprint does offer WiFi Calling: »
support.sprint.com/suppo ··· f6a91f67However, it only works on certain Android devices. iOS is not yet supported.