Bottom line: Although not entirely unexpected, AT&T's pricing would suggest that consumers will pay a premium to connect to faster 5G networks versus today's 4G LTE service. Pricing will likely level out as coverage expands and older networks are phased out but that could take years to happen.

AT&T on Tuesday said it has activated its mobile 5G network in parts of 12 cities across the country. The network won't be available to use until December 21 and even then, only on a very limited basis. Here's everything you need to know.

The first dozen cities to get AT&T's 5G network include Atlanta, Charlotte, Houston, Dallas, Jacksonville, Indianapolis, Louisville, New Orleans, Oklahoma City, San Antonio, Raleigh and Waco. In the first half of 2019, AT&T plans to expand the service to parts of Las Vegas, Nashville, Los Angeles, Orlando, San Francisco, San Diego and San Jose.

AT&T through an "initial offer" will invite select businesses and consumers to try out its 5G network. Customers will get complementary service for at least the first 90 days. After that, the requisite Netgear Nighthawk 5G Mobile Hotspot will cost $499 and service supplying 15GB of data will command $70 each month. There's no annual commitment, AT&T said.

Verizon launched a 5G home broadband service in four cities earlier this year.

An AT&T spokesperson told The Verge that the hotspot will offer peak theoretical speeds of 1.2 Gbps although "actual speeds will be lower." At a conference earlier this month, the carrier demoed a 5G network with speeds that topped out around 140 Mbps.