Sonim XP1 - yellow (unlocked) review: Sonim XP1 - yellow (unlocked)

In the age of cell phones as fashion accessories, the demand for rugged, durable handsets has remained decidedly small. But even though they constitute a niche market, fans of burly models are particularly vocal. For much of its life Nextel has mastered this sector well, with Sanyo and Casio contributing the occasional CDMA handset. Thrill-seeking GSM users, however, haven't been as fortunate. Though Nokia offered the Nokia 5100 and 5140 a while back, the selection of sturdy GSM handsets has remained limited. That is, until now. Sonim Technologies, a Silicon Valley-based company released the Sonim XP1 last year. Billed as the "world's toughest phone," the XP1 is indeed built like a tank. A hard shell and rubberized sidings protect the XP1 from bruises, and it meets military specifications for water, dust, salt, fog, humidity, transport shock, and thermal shock. No, it may not be pretty but it is built to last.

The XP1's feature list is pretty short; you won't find a camera, music, or Bluetooth, but you will find a vivid display, messaging, and a simple interface. As the handset is optimized for the European market (thank Sonim for remembering your home country), the XP1 lacks support for one North American band (GSM 850). Using T-Mobile's network we got decent call quality in San Francisco but with either T-Mobile or AT&T, reception will vary outside of rural areas. The XP1 is available as an unlocked model with Expansys for $359.

Design
We can confirm that the XP1 won't win any beauty contests. It's big and hefty (4.45 inches by 1.97 inches by 0.87 inch, and 4.52 ounces) with a boxy profile and a gaudy yellow-and-black color scheme (a more subdued gray-and-black version is available). But don't count its ugliness against it as that's really the whole point of the XP1. Rather than try to be stylish and sexy, it prides itself on being a brick of a phone that can take a lot of punishment. Indeed, we threw it around a few times without any problems. A YouTube video shows the Sonim XP1 being thrown from a building and run over by several cars without incident; it finally breaks after being quashed by a tractor. Unfortunately, we couldn't repeat those tests--we have to return it intact or we're out $359--but it certainly was one of the sturdiest phone's we've ever seen. And even with all that heft, it still has a comfortable feel in the hand and slips comfortably into all but the smallest pockets. It's worth noting that the XP1 is water-resistant and not waterproof. It won't survive a dunk in the water like the G'zOne Type-S, but it will survive quite a splash.

The XP1 is a tough and strong phone.

While many of Nextel's handsets have tiny, low-resolution displays, the XP1 has a bright, clear display that's easy on the eyes. It measures a spacious 1.75 inches (128x160 pixels) and supports 65,000 colors. The menu interface is simple and easy to use, and graphics looked reasonably sharp. You can change the backlighting time but no other options are customizable.

The navigation array is spacious and well-designed. The primary controls are four directional keys surrounding a central OK button. The keys are large and easy to distinguish but we wish they were raised just a bit more above the surface of the phone. Still, they're tactile enough, and we had no issues with misdials. The directional buttons double as shortcuts to the phone book, the messaging menu, the calls list, and the Web browser. Below the array find two soft keys, the Talk and End/power buttons, and the numeric keypad. All keys are slightly beveled, which makes it easy to dial by feel. They could have a brighter backlighting, however.

The ports on the bottom of the XP1 are covered by a rubber flap.

On the left spine you'll find tactile volume buttons and a nifty "easy call" key. Pressing this key in standby mode directly opens the phone book, which you can scroll through using the volume controls. After you find your desired contact, you can ring them with one touch of the easy call key. On the right spine is a small antenna port that's protected by a rubber flap. If desired, you can connect an optional external antenna to this port for better reception in rural areas. A 2.5mm headset jack and a mini-USB/charger port sit on the bottom of the phone; they're also covered securely by a rubber flap. A speaker sits on the rear side of the phone just above the battery cover. The battery cover has a locking mechanism that you can remove with a screwdriver or a sharp fingernail.

The Sonim's battery cover has a locking mechanism.

Features
The Sonim XP1 has a 500-contact phone book with room in each entry for five phone numbers, an e-mail address, a street address, and notes. Personalization options are slim here. You can't pair contacts with a photo, and only caller groups can be assigned one of five polyphonic ringtones.

Otherwise, the XP1 concentrates on what a phone should do. It eschews multimedia features in favor of the basics. Inside you'll find text messaging, a vibrate mode, a calendar, an alarm clock, a calculator, a voice recorder, a stopwatch, a countdown timer, and a world clock. There's also push-to-talk support and a speakerphone, which you can activate only after you place a call. The lack of a camera or music player isn't bothersome but we will knock our review model for not including Bluetooth. Sonim says the feature exists on other XP1 models but we couldn't find it on ours.

You can personalize the XP1 with a variety of color themes, wallpaper, and greeting messages. If you want additional ringtones, you can download from the WAP Internet browser. The XP1 does not offer any games or any kind of features aimed at construction workers, outdoorsy types, or extreme sports enthusiasts. A small flashlight would be really nice.

Performance
We tested the XP1 in San Francisco using T-Mobile service. Call quality was generally satisfactory. The volume level was high, and we enjoyed a clear signal free of static or interference. Voices sounded natural for the most part, though occasionally the audio was slightly harsh. This was especially true with deeper voices but it wasn't enough to sour our experience. As we noted previously, reception will vary without the GSM 850 band, so if possible we recommend testing the XP1 in your home area before buying.

On their end, callers said we sounded fine, though a few of our friends said the phone picked up a fair amount of background noise. On the other hand, automated calling systems could understand us in relatively noisy conditions. Speakerphone calls were decent. The speaker on the rear face has good output, though voices sounded garbled at times.

Sonim hasn't released battery life ratings, but our tests reveal a talk time of 7 hours and 48 minutes. The Sonim XP1 has a digital SAR rating of 0.60 watt per kilogram.