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Caterpillar, which makes monster-size trucks, now has a monster of a phone. Designed for construction workers or anyone working in harsh environments, the Cat S40 promises rugged protection from dust, drops and water. It runs Android Lollipop and comes with a generous-size battery as well. But for its $400 price, the Cat S40 should offer a better camera and more speed.
Design: Built to Last
With a rubberized back and solid-metal chassis, the Cat S40 looks like the phone Bob the Builder would use.
Unlike the rounded rectangles or rectangular blocks we see on smartphones today, the Cat S40 has a somewhat hexagonal shape that gives it a unique look. Its silver edges add a touch of class to what would otherwise look and feel like a truck tire.
A dedicated button in Caterpillar's trademark yellow on the phone's left side lets you turn on the phone’s flashlight by default, but you can program it to launch a specific app, wake the device or start the Google app.
Along the right edge are securely covered microSD, nano SIM and micro USB slots, and three black, ridged buttons for volume up, down and power. Below the device's 4.7-inch display are three physical keys for Back, Home and All Apps.
All the buttons are easy to find and press while you're wearing gloves, although they require some force to depress, but the covers for the USB and card slots are trickier to open with work gloves in the way.
Measuring 5.7 x 2.9 x 0.49 inches, the Cat S40 is smaller but thicker than the Google Nexus 5X, the Motorola Droid Maxx 2 and the 0.34-inch Galaxy S6 Active. The S40 has a smaller 4.7-inch screen compared to the other phones, though.
At 6.52 ounces, the Cat S40 is also heavier than your typical Android phone. Only the 6.2-ounce OnePlus 2 and 6-ounce Maxx 2 approached its weight. The extra weight is noticeable compared to today's smartphones, but because of the phone's rugged build, it felt justified.
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Ruggedness and Water Resistance: Impenetrable
This phone can take whatever you throw at it. The Cat S40 is certified drop-proof up to military spec MIL-810G, meaning it's supposed to withstand drops from up to 5.9 feet onto concrete surfaces. It's also designed to continue working in extreme temperatures, ranging from minus 13 to 131 degrees Fahrenheit.
I dropped the S40 from roughly 6 feet high onto a stone surface several times, and it came away without a scratch. However, unlike the Droid Turbo 2, the screen on the S40 isn’t shatterproof.
With a water and dust ingress rating of IP67, the S40 is dustproof and waterproof, able to withstand a dive in up to 3.3 feet of water for up to 60 minutes. We dunked the device in a foot of water, making sure to check that all the ports and flaps were closed before doing so. An hour later, I took the S40 out of the water, and it still worked perfectly.
To make it more convenient for construction workers clad in safety equipment, the S40's Gorilla Glass display can recognize your touch even if you are wearing gloves up to 4 mm thick. With Glove mode on, I launched apps and easily swiped through pages while I was wearing my gloves.
The screen will also detect wet fingers, so you can use the phone in the rain or under water.
Display and Audio: Just Alright
At 4.7 inches and just 960 x 540 pixels, the S40's touch screen is small and low-res by today's standards. A 720p trailer for Star Wars: The Force Awakens was colorful enough to show off the BB-8 droid's bright orange stripes, while Darth Vader's mauled helmet was clear. Viewing angles were limited, though, as images washed out when I turned the phone from side to side.
The S40 is designed to be bright enough to see even under the scorching sun at outdoor construction sites, and it lives up to that promise. Registering 566 nits on our light meter, the S40's display is more luminous than the average smartphone and Galaxy S6 active (547 nits). However, the Cat phone doesn’t match the Droid Maxx 2.
Displaying a respectable 102.9 percent of the sRGB color gamut, the S40 has a richer screen than the Maxx 2 (98.1 percent), but can show fewer colors than the average smartphone (117.5 percent), including the Nexus 5X, the OnePlus 2 and the S6 active.
With a Delta-E error rating of 2.5, the S40 produces more accurate hues than the average smartphone, but competing phones get closer to a perfect 0.
The Cat S40's bottom-mounted speaker was just loud enough to fill a small meeting room, but the music it pumped out sounded tinny. Drake's Hotline Bling came across as flat and metallic, while The Darkness' I Believe In A Thing Called Love jangled unpleasantly.
Software and Apps: Tailor-Made for Outdoor Workers
Running the relatively outdated Android 5.0.1 Lollipop, the S40 has very few differences from stock Android. In addition to the Play Store, Cat offers its own app store called App Toolbox, which Caterpillar created in collaboration with Appland to provide a curated selection of apps tailored to workers.
App Toolbox contains such lists as Construction Apps and Farming Apps, as well as such titles as Mining Weekly, Track Construction Equipment, ViewRanger GPS and Trails.
Caterpillar also tossed in its own Cat Phones tool, which looks like an app but actually opens the Cat support website in the browser. It makes looking for help a bit more convenient than having to search for the website in the default browser, but the approach is also somewhat misleading.
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Performance: Slow
Like a truck racing a car, the S40 cannot outperform its competition. Equipped with a feeble 1.1-GHz Snapdragon 210 CPU with just 1GB of RAM, the Cat S40 wheezed its way through many tasks. Closing the 10 apps I had open caused the phone to pause, while opening a complicated PDF document took 28 seconds — more than the 15.6 seconds it takes the average smartphone. Although swiping through home screens was smooth enough, launching games such as Drag Racing introduced lag.
Scoring just 1,019 on general-performance test Geekbench 3, the S40 lost to the average smartphone (2,758), as well as the octa-core-armed Maxx 2 (2,170). The S6 active is about five times faster, but it’s also more expensive.
The Cat S40’s Snapdragon 210 CPU wheezed its way through many tasks.
Don't expect to enjoy rich 3D games on the S40, either. Notching just 4,338 on 3DMark Ice Storm Unlimited, the S40 delivered graphics performance that’s about three times worse than the average phone.
Cameras: Not So Sharp
The S40's 8-megapixel rear camera is capable of delivering fairly good images on location, but it doesn't offer the kind of detail and color accuracy more premium handsets deliver, such as the 16-MP Galaxy S6 active or the similarly priced Maxx 2 (21 MP).
My shot of a Manhattan building against the sky was clear, but the blue sky looked paler than it did in real life. Ridge details on the edge of the roof were crisp.
At night, the S40 struggled to produce sharp shots. While my pic of Manhattan streets at night was bright enough for me to see individual windows on a dark building, the image was blurry and marred by flares from streetlights.
The 720p (highest resolution the S40 can record) video I shot of a busy cafe was bright, colorful and smooth.
Selfies I shot with the 2-MP front camera were splotchy and speckled, with my bright, peach-colored sweater looking like a pale, pastel pink and appearing more fuzzy than furry.
The S40's camera app gives you control over settings such as ISO light sensitivity, exposure compensation and focus mode, which is more than what the standard Android camera app offers.
Battery Life: All Day Long
Packing a generous 3000-mAh battery, the S40 will last you all workday long and then some. The handset clocked 9 hours and 42 minutes on our battery test (Web surfing over AT&T's 4G network at 150 nits of brightness), beating the average smartphone (8:13) and the OnePlus 2 (8:07). However, the Droid Maxx 2, the Galaxy S6 active and the Nexus 5X all lasted longer.
Bottom Line
Built to withstand harsh environments, the S40 is certainly one of the most rugged phones we've tested, surviving everything from drops to dunks. It also offers solid battery life. But its lackluster cameras and low-res display make the $400 price harder to swallow.
If you don’t need something that’s as sturdy as the S40, consider the Droid Maxx 2, which has superior cameras, better performance and a sharper screen. Note that the Droid is just water-resistant, not waterproof like the Cat S40.
Those willing to splurge should take a good look at the $549 Galaxy S6 active. It’s waterproof and rugged, and it boasts excellent cameras, a long-lasting battery and speedy performance. However, the Samsung is rated to survive drops from 4 feet, compared to 6 feet for the Cat S40.
Overall, the Cat S40 is a solid phone that can take a beating, so long as you don’t mind some lag.
