The spotty 5G rollout

If cities are only as "smart" as the data zipping between sensors and devices, the "smartest" places will be those equipped with the speediest broadband service to ferry the ever-expanding streams of data.

What's happening: All 4 national wireless companies have installed 5G service in parts of cities. T-Mobile, for example, released a 5G "boost" (if they have the Galaxy S10 5G phone) in parts of Atlanta, Cleveland, Dallas, Las Vegas, L.A. and New York on Friday.

But there are few 5G devices available, and coverage is extremely limited because the signals can't travel far. So T-Mobile, like other carriers, reverts back to its 4G LTE network in areas where 5G isn't available.

• Plenty of smart city features, like parking spot sensors, can be built with older wireless technologies, too.

At least at first, it will be affluent people who'll be willing to buy new 5G-compatible phones and pay any additional charges. That means the well-off neighborhoods are likely to be first to get 5G, with those pockets of coverage slowly branching outward.

• Experts worry there won't be equitable coverage in lower-income neighborhoods, or in spread-out residential areas that aren't near "anchors" like hospitals or office parks that will be early adopters of 5G.

The bottom line: Most metros are likely to have a handful of small "smart districts" far before they become "smart cities."

Go deeper:

• Special report: The human hurdles to smart cities
• Making cars pay to drive on the roads
• Take-offs and drive-offs
• The dangers of over-hyping 5G