The past week has seen some eye-popping new technology, including foldable phones from Samsung and Huawei and the HoloLens 2 mixed reality headset from Microsoft. But these breakthroughs have also come with equally jaw-dropping price tags.

Why it matters: Tech innovations often start out at prohibitively high prices. The fact that the technology exists in a commercially deliverable form practically guarantees that it will become affordable in a few years.

• If there's one thing the tech industry has mastered, it's turning today's high-end, high-priced luxury into tomorrow's affordable necessity.
• These new products show that two important technologies are well on the way to consumers' hands, even if right now they remain a bit out of reach.

Folding screens: The notion of smartphones with foldable displays has been around for a while. Such screens first showed up in devices with curved but relatively fixed phones, including the Galaxy Round and LG Flex back in 2013.

• Fast forward a few years and display technology now makes possible a device that can fold.
• The real breakthrough will be when this technology is not just cheaper, but even more flexible. Imagine something that can unfold like a newspaper or wrap around your wrist. To get there, we need other innovations, like batteries that are as flexible as the displays.

AR and VR that you actually want: The HoloLens 2 was the most talked-about new product launched at the MWC trade show, and for good reason. It addresses two of the biggest criticisms of the original model — its limited field of view and cumbersome fit. The new model also builds on its predecessor with improved performance.

• Also impressive is another mixed reality headset, introduced a couple weeks ago by a Finnish startup called Varjo. They have produced a headset that offers far better resolution than anything else on the market.
• As with the other products mentioned above, the price of Varjo's VR-1 is hardly consumer friendly. At $6,000, Varjo is targeting business customers. But the kind of screen resolution it's offering could be what it will take for consumers to be willing to spend significant periods of time in VR.

The bottom line: For real tech enthusiasts, eras in which everyone can afford to buy the latest and greatest are a little dull. The real thrills happen when there are products on the way that are out of your reach — because they won't be for long.

Urban sensors are often used to monitor illegal activity — from identifying drivers that run red lights to generating predictive crime maps — but they can also collect data for quality-of-life improvements like reducing emissions and preventing car accidents, writes Karen Lightman for Axios Expert Voices.

The big picture: Municipalities could use anonymized, secure sensor data in combination with advanced computing to better understand how people travel through and use public space, without sacrificing individual privacy.

What’s happening: Academic researchers and urban planners can leverage the latest sensors — including “camera-as-sensor” technologies, which convert a camera’s optical image into an electronic signal — to gather and share insights about roads, intersections and public spaces.

• Yes, but: Ensuring the data collected is protected and anonymized will be crucial to earning public trust in these efforts.

Details: These projects rely on a combination of video streams, computer vision, AI, and edge computing (computing done near the data source, not in the cloud).

• Metro21: Smart Cities Institute at Carnegie Mellon University collaborated with Urban Data Eye and the Pittsburgh Downtown Partnership to identify pedestrian movement patterns based on CCTV footage and live-streaming. It found that furniture and tree placement impact where pedestrians congregate, which could inform planning decisions.
• Platform Pittsburgh, another Metro21 project, analyzed urban video streams to identify frequent sites of near-miss accidents, which could guide the creation of safer intersections. It's also tracking emissions based on images of truck's tailpipes.
• Numina has partnered with city planners, mobility companies, and other stakeholders in Jacksonville, Las Vegas and St. Louis to collect and analyze data on the walkability and bike-ability of urban areas using light-post-mounted sensors and computer vision.

This technology has applications outside urban areas, as well. Project Diversita developed a camera and computing system that can identify over 5,000 different animal species to inform wildlife research and management.

The bottom line: Applying machine learning and edge computing to sensor and camera data could inform future urban planning initiatives, the allocation of public space, and even conservation efforts.

Read more of the full piece by Lightman, who's executive director of Metro21.

Let us know what you think of Axios Expert Voices, where we help vetted experts write in our style on topics driving the conversation.

A series of hearings on Capitol Hill this week may reveal how lawmakers are leaning when it comes to federal privacy legislation, Axios' David McCabe reports.

Why it matters: Industry groups have been pushing Congress to take action that would override a growing number of state privacy laws, led by regulations set to go into effect in California next year.

Driving the news:

• A House Energy and Commerce Committee hearing today will feature industry representatives and consumer advocates.
• A Senate Commerce Committee hearing tomorrow will feature trade groups for tech and telecom companies, but not public interest groups.

What to watch:

• Timing: Top lawmakers on both panels may signal when they expect to introduce legislative proposals. A group of senators working on bipartisan legislation has yet to confirm, for example, when it will release its legislation.
• Preemption: One of the hottest debates on Capitol Hill is whether Congress should override state rules, with Democrats indicating they'd only agree to do so if a national law was appropriately tough. Lawmakers representing California — including House Speaker Nancy Pelosi — have expressed an interest in protecting states' rights to enforce their own privacy rules.
• Scope: Much of the privacy debate has centered on Silicon Valley and Facebook in particular. Will lawmakers continue that trend or more aggressively ask questions about other industries, like retailers and DNA tests that also produce sensitive consumer data?

The other coast: California Attorney General Xavier Becerra and a state lawmaker introduced a bill to make changes to the state's forthcoming privacy rules following public forums on the issue, including an expanded ability for consumers to sue companies over privacy issues.

• Common Sense, a consumer advocacy group, said it supported the changes.

The bottom line: So far, the privacy debate in Congress has seen a lot of press attention and not much movement. Despite a year of discussion about these issues on Capitol Hill, it's still just the beginning of what could be a protracted legislative process.

Investigative reporting from news outlets over the past 2 weeks has led to some swift changes from some of the biggest social media companies, Axios' Sara Fischer reports.

Why it matters: Despite an onslaught of hearings and statements from Washington, virtually no regulation has actually passed in the past couple of years to significantly address the potentially harmful practices of tech companies. Media reports have driven most changes to date, especially around privacy.

• Facebook says it’s working on an improved compliance and audit process for the third-party contractors that moderate content on its platform, following a brutal exposé Monday by The Verge's Casey Newton on workplace conditions at a facility in Phoenix, Arizona.
• Popular health and fitness apps have stopped sharing data with Facebook after a Wall Street Journal report last week detailed how many do so without users knowing.
• Facebook will shut down its controversial Onavo VPN app in the wake of backlash following TechCrunch’s investigation about Onavo code being used in a Facebook research app that sucked up data about teens.

Be smart: These actions come as regulators begin meeting on Capitol Hill enter a series of hearings this week. But, as Axios' David McCabe notes, "The privacy debate in Congress has seen a lot of press attention and not much movement."

My thought bubble: Changes without the weight of law can be temporary, or promised but not delivered. Remember that "clear history" feature Facebook promised? We're still waiting for it to arrive.

On Tap

• Mobile World Congress continues in Barcelona, while the New York Times' New Work Summit wraps up in Half Moon Bay, California.

Trading Places

• Former PepsiCo CEO Indra Nooyi has joined Amazon's board of directors.

ICYMI

• Apple has been testing sleep tracking features for Apple Watch and could add them to the product by next year. (Bloomberg)
• Sprint's 5G network will launch in the first cities in May, while T-Mobile doesn't expect a broad launch for 5G until the second half of the year, when devices that support all its frequencies are available. (The Verge/CNET)
• Facebook restored a number of Russia-linked pages even as it wrestles with how best to deal with state-created content. (CNN)
• The SEC wants to hold Elon Musk in contempt for failing to live up to the terms of a settlement over his tweets. Musk, meanwhile, has indicated his contempt for both the settlement and the SEC itself. (Axios)

Check out these harvest mice napping in flowers.