Car technology is growing by leaps and bounds, and automobile buyers are responding by basing more of their purchasing decisions on tech. But as advanced as car tech has become, it’s still held back in part by the lag time between the rapid pace of change in consumer electronics and the years-long production cycles in the automotive realm.

That’s starting to change, however, as automakers move more toward software-based infotainment systems and a combination of tethered smartphones and embedded cellular modems to deliver connected content and features. Ford kicked off this trend with its Sync system in 2008, the first to allow software upgrades. It marked the first time consumers could buy a car one year and add infotainment features that were rolled out the next -- without having to buy a new vehicle.

In the case of Ford's Sync, the car owner has to download the software for the new feature from the Syncmyride website onto a USB drive, then upload it through the car’s USB port. The process is pretty simple, and technophobes can have a dealer do it for them.

Now, two very different vehicle brands – Mercedes-Benz and Ram – are making it even easier by providing over-the-air updates.

With the launch of its mbrace2 system starting in May with the new SL65 Roadster -- and, later, in all 2013 vehicles -- Mercedes will be the first to offer over-the-air updates. It helps that mbrace2 is a second-generation system and that the vehicle already has a cellular modem. The original mbrace system provided safety services such as automatic crash notification and emergency assistance, as well as convenience features such as door unlocking and locking via a smartphone application.

With mbrace2, Mercedes-Benz adds Internet access and Google Local Search as well as in-dash apps for Facebook and Yelp. And if the automaker decides to add features in the future or update the system’s software, it can be done over the air without drivers having to do anything save, perhaps, updating the app on their smartphone.

Ram trucks may seem an unlikely brand to be on the cutting edge of technology, but Ram representatives told us that owners such as contractors use their pickups as a mobile office and need to stay connected. That’s why at the New York International Auto Show last week, Ram introduced a new UConnect system for the Ram 1500 that features built-in cellular connectivity courtesy of Sprint.

The system will provide emergency services when a 911 button on the rear-view mirror is pushed, and owners will automatically receive regular vehicle health reports. They’ll also be able to remotely lock or unlock the truck’s doors, start the engine and flash the lights using a smartphone app, or from the Web.

Ram says the software and applications for the system can be updated over the air, and as they become, available new apps can be downloaded directly to the dashboard, “so features remain current.”

At the New York Auto Show, Lexus also showed us its updated Enform system and accompanying Enform app in the new GS 350. A Lexus representative explained that the system will stay current as the app is updated.

With automakers adding telematics system similar to GM’s OnStar at a record rate in the past few years -- and millions cars coming off the assembly lines with built-in cellular modems -- many more vehicles could soon have this capability. If they don’t, they’ll be left behind by models with infotainment systems that can be updated easily and automatically -- not to mention passed over by increasingly tech-savvy, constantly connected car buyers.

Doug Newcomb has been covering car technology for more than 20 years for outlets ranging from Rolling Stone to Edmunds.com. In 2008, he published his first book, "Car Audio for Dummies" (Wiley). He lives and drives in Hood River, Ore., with his wife and two kids, who share his passion for cars and car technology, especially driving and listening to music.