For the last five months, my most used iPhone app has easily been stream aggregator WunderRadio, which has emerged as the preferred way to stream a lot of different radio stations on-the-go. I’ve downloaded the various free apps offered by the broadcast groups, but I usually gravitate to WunderRadio for its one-stop shopping. And because I’ve already bought WunderRadio, and competing stream aggregator apps aren’t free, I haven’t had much impetus to experiment. (I have tried the very different Tun3R, which, as its name implies, seeks to replicate radio’s dial-scanning experience, but specializes in streams of pureplays and more eclectic terrestrial stations.)

But I have an interest in anything that Livio Radio’s Jake Sigal does. He’s the inventor of the USB turntable—probably my most-used gadget until the iPhone. I downloaded Livio’s app almost immediately after its May 10 release. Livio’s app sells for $4.99 vs. WunderRadio’s $6.99 (at the pricy end of similar apps). Both are built around RadioTime’s influential stream directory, but Livio is promising 42,000 stations while WunderRadio claims 36,000. And Sigal’s app is positioning itself as the first “developed from the ground up for use in a car.”

To that end, the calling card for the Livio app is its suite of six programmable car radio-style punch buttons, which allow you to go from one station to another without going to a longer favorites list. (My WunderRadio list alone is more than 100 stations.) The buttons are finger-size—larger than the usual tiles in most apps’ station listings, where it’s always easy to punch an adjacent button unintentionally. The app also has a finger-sized “dial” display, which promises to choose a station in a similar genre when swiped. And a station’s “now playing” information is given the largest, most prominent display.

The ease of use of the push buttons is certainly seductive, and Livio’s most compelling feature. On future versions of the app, in fact, you hope there’ll be the ability to set multiple suites of buttons and toggle between them. Having to limit yourself to six stations at a time when your car radio gives you 18 is not an infinite dial. (Sigel says there isn’t presently space for a function button to let users toggle between suites.)

I tried the swipe feature a few times. Station recommendation on aggregator sites often tends toward pureplays or exotica. On the Livio app, when I swiped the “find button” while listening to Top 40 KAMP-FM (Amp 97.1) Los Angeles, it took me to KHTC (96.3 Now) Minneapolis—clearly a station of similar construct. Then I swiped again and ended up at two all-Beatles stations. And swipes from other Top 40 stations took me to Oldies or Urban AC stations (or back to the Beatles).

The “dial” display also features a six-digit number for the station now playing, and tapping the dial gives you the chance to go to another station by entering their station code. Sigal says the intent here is to allow users to tweet a station, rather than making another user try to figure out which of, say, multiple Jack FMs was the one being recommended.

There were a number of early bugs in my week with Livio. Punching from one station to another or using the swipe button sometimes caused the app to abort. There was also at least one station that seemed to be playing at the wrong speed; (it worked fine when I tried it elsewhere). “Now Playing” information didn’t always update: one station showed that it was playing Drake when it was actually in Michael Bublé; (the Drake song was left over from a previous listen, but I’d already been through several songs in the new session). And because Livio restricts itself to RadioTime streams, which WunderRadio doesn’t, there are no Clear Channel stations.

Finally, Livio is more like your car’s GPS than its tuner in one key way. Livio makes you acknowledge its disclaimer, “do not program or use the software until the vehicle has come to a complete stop” every time you open the app. (Emphasis mine.) While not programming-and-driving is pretty obvious, the whole positioning of the app would seem to imply that the punch buttons aren’t any more distracting than your AM/FM buttons. (And while I seem to remember seeing a similar disclaimer on Pandora, I didn’t get it when I last opened the app.)

Livio is on the right track in its intent to bring a non-tech’s frame-of-reference to the car radio’s infinite dial – the selling point of its tabletop tuner as well. And anything that tries to give radio stations the existing ease of iPhone use of Pandora should cheer other broadcasters. (That said, the screen shots in the app store and a lot of my recommendations focused on other Pureplays.) And I’m definitely looking forward to the next version—not to mention seeing if more apps try to replicate Livio’s dial experience.