Calling the Sonim XP3 Enduro ugly doesn't seem entirely accurate. Sure it's twice as thick as Apple's iPhone and covered in garish yellow plastic, but it at least has character — albeit a burly, gruff Army Reservist kind of character. With its deep plastic ridges, exposed screws and machine-like vents, the XP3 looks more like an accessory to an electric drill than a relative of most modern mobiles.
The XP3's screen is an underwhelming 1.77 inches diagonally, with a below average 128x160-pixel resolution. Below the screen is a set of keys dedicated to navigation and shortcuts and a standard 12-button numeric keypad. Though the screen may be under par, the button size and placement is excellent, with large raised keys giving good definition for easy input.
Around the ruggedised chassis we find four extra shortcut keys. Two of these adjust the volume controls, a button on the left is dedicated to opening your contacts list and there's one on the right that activates the flashlight on the top of the handset. On the bottom of the phone are a 2.5mm headphone socket and a mini-USB port for charging and PC transfers.
As you will read in the next section, the XP3 is light on modern phone features beyond the basic PIM functionality. But then, this isn't the phone for latte-sipping, Italian shoe wearing, eye-bag moisturising city dwellers — this is a phone for people who tend to get themselves and, as a result, their phone dirty. Sonim offers a three-year unconditional guarantee that the phone will withstand the following list of tech-abuse.
Firstly, the XP3 carries an IP-57 certification, meaning it conforms to certain levels of resistance in line with the Ingress Protection rating system. The 5 in that figure indicates the phone is protected from dust and sediment, allowing only limited levels of dirt beyond its tight, plastic walls. The 7 indicates that the phone can be submerged in water up to one metre for 30 minutes.
The phone is also resistant to shock, with Sonim specifying its tolerance of shock-drops up to 2 metres onto concrete. The screen is likewise shock and glare resistant. The XP3 also meets the US military certification MIL-810F demonstrating its ability to endure periods in unfavourable weather and environmental conditions including rain, fog, humidity, extreme temperatures and salt air.