In the app era, radio has gone Wi-Fi and 3G

Remember when listening to radio­ meant tuning in to AM or FM? These days, I do most of my listening via Wi-Fi or 3G.

With Internet audio apps such as Pandora and Spotify, any smartphone can pull in ­music, news, and sports from around the world. But sometimes you want something close to home — your favorite hometown sports talk show, or local news and weather updates. Luckily, there are plenty of audio apps that tune into traditional radio­ broadcasts, offering features you won’t find on that bedside clock radio.

Three of the best, Stitcher, iHeartRadio , and TuneIn Radio Pro, deliver an appealing mix of traditional radio and Internet podcasts.

A fourth, DAR.fm, is a curious but clever service that serves as a kind of DVR for your favorite radio programs.

Start with Stitcher, a free app for iPhones and Androids with a clean, simple interface. You can go directly to a news section that hooks you up with audio feeds from major network news shows such as “60 Minutes” and the “NBC Nightly News.” A special section is entirely devoted to 2012 election news, and there are podcasts aplenty on pretty much every topic.

And of course there are links to hundreds of US radio stations.

For something a little fancier, there’s iHeartRadio, a free app developed by the radio conglomerate Clear Channel Communications to feature its own stations. Luckily, iHeartRadio has lots of other listening options. For instance, there are streams devoted to a variety of genres. One plays only music by the Beatles and Rolling Stones, while another features California surf music. Besides, iHeartRadio borrows Pandora’s best-known feature and lets you build customized music channels. Tell it you like Adele, and you get a constant stream of songs from her and from similar tunesmiths.

I wrote about another of these services, DAR.fm, more than a year ago, fully expecting the major music companies to crush the service with piracy lawsuits. But it’s still there, and still cool.

Open a Web browser, go to DAR.fm, and sign up for a free account. Then search the site for your favorite radio stations and shows; thousands are listed. Say you want tomorrow’s broadcast of the Jim Rose sports talk show. Just click “record.” DAR.fm will do exactly that and save the recording in your account. Now get a free DAR.fm app for your iPhone or Android device. It downloads the recorded show so you can listen whenever you like.

A free DAR.fm account comes with 2 gigabytes of storage; the company says that’s enough for 100 hours of listening. But you can record only one program at a time. For $39.95 a year, you get 20 gigs of storage and the ability to record up to 10 programs at once.

Despite a clunky interface, DAR.fm works quite well. But for a far more polished music app, there’s nothing better than TuneIn Radio, an app for Apple and Android devices.

The free version of TuneIn Radio lists thousands of traditional radio stations around the world, sorting them by location and genre. You can share listening choices with your friends, through Facebook, Twitter, or ­e-mail. It also turns your phone into a clock-radio, with an alarm feature that wakes you to a favorite station. The free version’s plenty nice, but the pro edition, for a mere 99 cents, eliminates onscreen ads and lets you record shows to your phone. It’s an excellent deal.

Neither DAR.fm nor TuneIn Radio let you share recorded music with other devices; the big recording companies wouldn’t like that. But both offer­ a welcome way to avoid missing the shows you love.

Still, these apps have their limits. Bandwidth is the big one. Cell carriers Sprint Nextel Inc. and T-Mobile USA each offer unlimited data plans, so you can stream 3G music as much as you want.

But the nation’s biggest carriers, AT&T Inc. and Verizon Wireless, have backed away from unlimited plans. Constant listening to Internet audio streams can quickly burn through your data allotment with these carriers. So hook up your phone to a Wi-Fi Internet connection at home or work for a cheaper way to listen.

Even in the face of bandwidth caps, Internet listening continues to boom. Traditional radio stations are so nervous that they have asked Congress to require that all cellphones have built-in FM radios, in hopes that this will help them to attract more listeners.

They’d be better off urging smartphone users to download one of these excellent apps.