Harman Kardon GPS-510 4-Inch Widescreen Portable GPS Navigator and Media Player

4-inch WQVGA 480px x 272px high-resolution widescreen touch screen (actual size)

Once it knows where you are headed, the device offers you the choice of shortest distance or most use of freeways or other high-speed arterials. You'll also find a trip planner that lets you lay out and save multiple destinations, as well as avoidance choices for routing your trip away from borders, toll roads, unpaved roads, ferries, and more. If you take a wrong turn or need to use a detour, the GPS-510 will automatically re-route you and get you back on your way.

And how did the GPS-510 perform out on the road? In a word, admirably. The responsiveness of the device and excellent user interface make it a joy to use. The GPS-510 also has an extremely fast and accurate GPS signal processor, so it locks, calculates and recalculates routes, and responds to commands quickly. One of the hardest things for a manufacturer without a long history in building GPS navigators is getting the routing algorithms correct, so it was nice to see that Harman Kardon seems to have gotten this right. In most cases, the device decided on logical and efficient routes, too--something that can't be said of all GPS devices out there.

Intuitive interface is easy to operate. See route planning details.

Easy to understand traffic data

Interacting with the GPS-510's touchscreen is delightfully intuitive and reliable; there's really no need for a stylus or navigation buttons, which simplifies things on the road. The division of the main interface into four main quadrants is a helpful touch, and it's refreshing to see manufacturers moving away from awkward icon-based menus. Instead of drilling down through lists of icons, all of the GPS-510's options are presented on simple, color-coded shapes. That said, we were a little puzzled by the use of the "Source" menu key, which takes the user back to the main menu from any point in the interface. It's a useful feature, but why not call this the "Home" button instead?

The screen itself is sharp and clear, offering great resolution and clarity in all driving conditions. The map screen is a sight to behold, offering delightfully crisp 3D images, as well as excellent responsiveness when zoomed and panned. Likewise, the interfaces for music and video playback are pleasantly uncluttered, responsive, and well thought-out. One problem in our unit, though, was the lack of a sleep mode. The device's screen will stay on at full illumination when it's left idle--even when running on battery power. There's also no sleep button on the device.

Accurate, detailed 3D navigation, and turn-by-turn directions.

Use the unit's touch screen to enter address locations.

An intuitive menu lets you switch quickly between music, video, and navigation options.

Multimedia
The GPS-510 strives to be much more than just another GPS device in a crowded market, and that's likely why Harman Kardon has polished the multimedia features of the device so well. With support for MP3 and WMA music files, the music player has a refreshingly intuitive user interface and good sound quality. It's a cinch to browse music on your SD card by artist, album, genre, playlist, and song. Another nice touch is that you can keep the music playing while the unit is in navigation mode.

	Video playback is equally straightforward. The device recognizes WMV9 or MPEG-4 AVI video files and presents them in a scrolling list. Press a title and you're off in movie land, complete with smooth framerates and minimal jitters during high-action sequences. We did encounter a format incompatibility with an AVI file encoded in the DIVX format. Attempting to play the file freaked the GPS-510 out, and a hard reset was required. Harman Kardon is very clear about which file formats are supported, but many folks might inadvertantly attempt to play a DIVX-encoded AVI instead of an MPEG-4 AVI. Broader format support would be a welcome addition. To ease some of the pain of getting your movies and TV shows into the right format for the GPS-510, Harman Kardon provides a brief guide for Windows Media Player users. Mac users will have to use third-party media encoders to prepare their videos for the GPS-510. Lastly, battery life when playing back videos was surprisingly good. After a two-hour movie the GPS-510 was only down to a 40 percent charge.

The only button you'll find on the device is the recessed power button on the top, right next to the SD card slot. The slot accepts cards with up to 4 GB of capacity. There's also a small jog wheel on the right side for volume and display brightness control. Below this dial you'll also find a mini-USB port that serves double duty for both charging and PC-to-device data transfers, as well as a standard 3.5-millimeter headphone jack. Meanwhile, you'll find a pinhole reset button on the bottom, as well as a hold switch on the left side for deactivating the touchscreen. Lastly, the back of the unit sports a small audio speaker and a port for an optional GPS signal booster antenna.

Pros
Excellent user interface
Fast, accurate GPS performance; good mapping capabilities
Polished, user-friendly music and video playback