While it's not a 3.5G phone like its MicroSD-capable CU500 cousin, the CU400 does have support for UMTS, a 3G technology that lets it stream video and music much faster than non-3G phones. Cingular is certainly pushing this with the CU400, especially with its built-in access to Cingular Video, Cingular's 3G content portal with exclusive mobile content from channels like HBO Mobile, plus short clips from networks such as Cartoon Network, CNN, and Fox. Please read our review of Cingular Video for our full run-down of the service. The CU400 video player supports MPEG-4 and RealVideo formats, and you can download video applications such as MobiTV, which lets you watch live streaming TV. Not only that, but you can download other applications such as MySpace Mobile, which lets you keep in touch with your MySpace buddies on the road.
Although the CU400 does not have a digital audio player, you can still access streaming music via MobiRadio and watch streaming music videos on Music Choice. The CU400 also comes with MusicID, a song identification service that lets you know the title of the song just by holding the phone up to a music source, such as a radio. Other music services include Billboard Mobile for industry news, and The Buzz, which is an array of fan communities of certain artists. You can also download XM Radio Mobile if you happen to have an XM radio account so you can listen to satellite radio on the move. It's a shame the CU400 doesn't come with a dedicated audio player, but considering its lack of a MicroSD card slot, it's just as well.
The VGA camera on the CU400 is a considerable step down from the CU500's 1.3-megapixel camera. Camera options include three resolutions (640x480, 320x240, 160x120), three quality settings (Superfine, Fine, Normal), six white balance settings, four color effects, a multishot setting (up to nine shots), a self-timer (up to 10 seconds), and three shutter tones, plus a silent option. Picture quality was quite grainy and blurry, which is what we expected from a VGA camera. The video recorder has two different resolutions (320x240, 176x144) and camcorder options include the same quality, white balance, and color effects settings as with the still camera. We found the video quality to be grainy, choppy, and quite poor in general, but that is pretty normal for a camera phone such as this.
There are quite a few personalization options available for the LG CU400. Not only can you switch out the wallpaper and color schemes, you can also replace the graphics with those taken from the camera or download more from Cingular's Web site. Additional ring tones are also available for download from Cingular. The CU400 supports Java 2.0 games and comes with Diner Dash, World Poker Tour, Ms. Pac-Man, Platinum Sudoku, and Tetris preloaded in the phone, though you can always download more.
We tested the LG CU400 quad-band (850/900/1800/1900; GPRS; UMTS) phone in San Francisco using Cingular's service. Call quality was better than we expected, even in a breezy outdoor environment. Callers did notice we were using a cell phone, but that was not a big deal. You can only activate the speakerphone during a call, and it sounded a bit tinny when activated. As far as Bluetooth pairing goes, we managed to pair it with the Technocel T50 Bluetooth headset without a hitch. Though the UMTS speed is not nearly as fast as HSDPA, we still found it impressive. It took a bit long to connect to certain Web sites, and we suffered slight buffering issues when watching certain Cingular Video clips, but it wasn't unbearable. The video quality was a bit pixilated, but that's to be expected with such a low-resolution display. It took us about eight seconds to download the MySpace Mobile application. It's certainly not broadband speeds, but it's slightly better than dial-up.
The LG CU400 has a rated talk time of as much as 5 hours and a tested talk time of about 4 hours and 15 minutes. It also has a standby time of as long as 12 days. According to FCC radiation tests, the CU400 has a digital SAR rating of 1.14 watts per kilogram.