Your mobile phone can reveal a lot about you, from what you buy to where you eat. Now insurance companies want to tap into your phone to track how well you drive.

Do you have a lead foot or a long commute? Your mobile phone will tell.

Are you in the habit of Snapchatting behind the wheel? It will know.

Do you talk on the phone while changing lanes? It’ll be watching.

Piggybacking on sensors already built into many new smartphones that measure acceleration, direction, sudden falls, and location, insurers in Massachusetts and across the country are introducing mobile phone applications that monitor driving habits. The technology will allow them to base car insurance premiums on how well you drive.

Two companies recently asked the Massachusetts insurance regulator for approval to market the free apps to drivers in the state. But officials have many questions — including exactly how insurance companies will use the data they collect and who will have access to it.

The apps, which have been approved in more than 30 states, including Maine, Vermont, New Hampshire, and Rhode Island, are installed voluntarily by drivers. Insurance and technology companies say the apps are a tool to reward safe driving. At the same time, they also accumulate data on the dangers of distracted driving by tracking how often drivers text, call, or check social media behind the wheel.

“Every driver leaves his or her digital footprint,’’ said Robert Hartwig, president of the Insurance Information Institute, a New York-based industry group. “The idea is you install it and you forget about it. . . . And your auto insurance risk is being evaluated on a regular basis.’’

Think of these new apps as version 2.0 of the devices that insurance companies introduced nearly a decade ago that plugged into a car’s diagnostic system, such as Progressive Corp.’s Snapshot. But those devices — used to measure speed, braking, and travel distance — are expensive, clunky to install, and never really caught on.

Insurers hope that a mobile app accessible with a few swipes of a finger will be more popular and attract younger customers, eventually leading to insurance rates based on actual driving, rather than other factors, such as your ZIP code or what kind of car you drive.

Drivers have access to real-time data on their phones — showing them how often they were tailgating or speeding — providing a pocket-sized roadmap for improvement.

But these mobile apps have regulators in some states, including Massachusetts, scrambling to understand the technology.

“The division has privacy, accuracy, and availability concerns in regard to the smart phone applications,’’ said Chris Goetcheus, a spokesman for the Massachusetts Division of Insurance, which is in the early stages of developing policies for the apps. “The division understands . . . devices that can be installed in the vehicles. But introducing a smartphone app is a whole other ­arena.’’

State regulators say they probably won’t be ready to decide until the end of the year whether to allow the apps.

Drivers participate by downloading the program on their phones. As an inducement, most drivers are offered premium discounts of between 5 to 10 percent to sign up. Further discounts kick in for good driving. Insurance companies say that the current programs do not penalize participants for bad driving, but consumer advocates worry that could happen in the future.

Besides offering real-time data to help drivers improve, the apps also allow parents to keep track of their teen drivers once the app is installed on their phones. It could eventually be tied to other services, such as roadside assistance.

“Our customers today are more tech-savvy and on-the-go than they’ve ever been and they want information and insights in real-time,’’ said Dave Pratt, the general manager of usage-based insurance at Progressive. “Given our reliance on smartphones today, it was a natural evolution.’’

Progressive plans to start rolling out its mobile tracking app later this year.

Vance Loiselle, the chief executive officer of Boston-based TrueMotion, which developed the app for Progressive, said the software can identify if the user is a driver or a passenger, based on sensors on the phone that indicate which side of the car a driver enters, where he or she is going, or what time of day it is.

Progressive hasn’t filed a request to use the app in Massachusetts yet, butother companies have.

Both Illinois-based Allstate Corp. and Safety Insurance of Boston in recent months have asked the state’s insurance regulator for permission to market the free app to Massachusetts drivers. Allstate is already running television commercials nationwide featuring actress and comedian Leslie Jones, who will be in the new “Ghostbusters’’ movie, to promote its Drivewise app.

But Allstate and Safety’s applications are essentially on hold in Massachusetts while regulators develop policies to cover this new technology. State insurance officials have raised a slew of concerns about whether third parties would have access to the data the apps are collecting; if the information can be used in accident investigations; how consumers know if the records are accurate; and which phones can run the app.

Technology is expanding the data that can be collected on individuals and companies are getting ever more sophisticated about how they use the information — whether it’s mobile apps or new cars equipped with steering wheels that measure heart rates, said Robert Hunter, director of insurance at the Washington, D.C.-based Consumer Federation of America.

Consumers need to be aware of the information they are allowing insurance companies to collect, and what that can mean for their premiums, he said.

“It’s really important to know what you’re getting,’’ Hunter said. “I think anything that measures risk and makes people who are bad drivers pay more is good. But you have to know exactly what they’re measuring.’’

For some consumers, it’s a worthwhile trade-off.

Tim Solon, 29, plugged Progressive’s Snapshot device into his car when he moved to Boston from Indiana nearly two years ago after he was told that his premium would skyrocket. The device helped him reduce his premium by about $300 during his six-month policy duration and forced him to be a more careful driver, Solon said.

He is eager for a mobile app version, that would be easy to download and simpler to check.

“Saving about $300 was completely worth sharing those things about my driving,’’ Solon said.

Eventually, every major insurance company will be offering a mobile app that monitors driving, said Jeff Blecher, senior vice president of strategy at Medford-based Agero Inc., which provides roadside assistance software services to insurance companies and is testing its Driver360 app with half a dozen insurers nationwide.

“I think mobile is the way forward in the long run,’’ he said.

Deirdre Fernandes can be reached at deirdre.fernandes@ globe.com. Follow her on Twitter @fernandesglobe.