What's good: Design, battery life, connectivity options (3G, GPS, Wi-Fi, and Bluetooth)
What's bad: Reception in some areas, proprietary ports
The Samsung Jack i637 is a nice entry-level device that will compete well with the Nokia E71x and other devices in AT&T's smartphone lineup. It looks good, and offers a good feature set to boot. Overall performance is good, and it offers a range of programs out of the box. Minus a few minor frustrations, our two primary issues came in the use of a proprietary ports and less-than-desired reception in spotty areas.
At first glance, the device looks sharp. Billed as an update to the Samsung BlackJack line, the i637 offers tapered edges and vaguely resembles its older brother, the Samsung Epix. Weighing in at 3.5 ounces, the device measures 4.4 inches tall by 2.4 inches wide by 0.5 inch thick. It fits well in the hand, and the chrome exterior design elements accentuate the device well. The chrome look did have a setback, however: because of the slippery nature of it, the battery back required perfectly dry hands to remove.
The 320x240 QVGA screen looks good and displays colors well, but we'll admit that we're a bit spoiled by the high-resolution screens found on devices like the BlackBerry Bold and the Curve 8900. However, given the Jack's appeal to the entry-level smartphone crowd, we understand. 
The keys on the keyboard are close together, making it challenging to type quickly for those with larger fingers. Additionally, the bottom row is a bit cramped with a small spacebar, and shortcuts to applications. Instead of pressing the comma button, for example, we would often press the AT&T Navigator shortcut button. The keys themselves feel good, and offer the right amount of firmness.
In its earlier days, Windows Mobile was well-known for its sluggish behaviors, particularly when running multiple programs. Not the case anymore. We were pleasantly surprised at how peppy the device was, even with multiple programs running in the background. Packed with a 528 MHz processor, 256 MB ROM, and 256 MB RAM, the Jack packs a punch. Along with the usual Windows Mobile 6.1 productivity suite, the device offers AT&T Music, Cellular Video, AT&T Mall, AT&T Navigator, AT&T Wi-Fi (offering free connectivity through 17,000 AT&T hotspot locations), Adobe Reader LE, MobiTV, WikiMobile, eBay, My-Cast Weather, and Office Mobile. Fortunately, the device will be upgradeable to Windows Mobile 6.5 at launch.
The Jack ships with a 3.2 megapixel camera and a portrait mirror. Though a flash isn't offered, pictures were generally good, provided they had the correct amount of light. On the other hand, video quality left a lot to be desired, as it appeared choppy and dark. Our favorite feature had to be the threaded text messaging, making it much easier to keep track of our conversations. One place where we have to give Samsung credit is the inclusion of 3G, GPS, Wi-Fi, and Bluetooth into the i637. It's nice to see a device that offers all of them.
The Jack is a quad-band device, meaning it supports GSM 850/900/1800/1900 and UMTS/HSDPA 850/1900/2100 bands. Despite its cosmopolitan offerings, reception was a bit spotty. In areas where AT&T service was strong, the phone performed well, and callers could hear us without a problem. But in areas where AT&T service was generally mediocre, the Jack had a challenge acquiring a consistent signal. Callers would complain that we were fading out, and calls were dropped on occasion. As a result, we would recommend taking advantage of the trial period if you live in an area with mediocre service. Data connectivity was a bit perplexing, as well: every now and then, the phone would switch from 3G to EDGE, making videos and other data-intensive things challenging to view. Both speakerphone and regular speaker quality was good; the volume could be a tiny bit louder, but that's only a minor complaint.
The Jack ships with a 1,480 mAh battery, capable of 7 hours of talk time and 12 days of standby time. In separate tests, we were able to receive just over 5 1/2 hours of continuous talking and 9 days of standby before the device powered down. Overall we were pleased with the battery life, particularly given the relatively short lifespan between the Jack's competitors. We did not test it with Wi-Fi and GPS on, however.
The Samsung Jack is a fantastic player in the entry-level smartphone realm, and will appeal to first-time buyers. It offers a number of features, and despite a few setbacks, proves to be a worthy competitor in the field. Check the reception and the keyboard before you commit to the two-year agreement, and you're likely to be pleased.
