Phone cases are boring. Adventurous, life-marrow-sucking souls are known to embrace the danger of carrying their iPhones case-free, begging fate to shatter those screens when running from bulls or jumping out of moving cars. But even more hardcore than carrying a naked iPhone is wrapping it in a badass case like one of these. Your boring silicone sleeve can’t see heat, or saw through wood, or build an IKEA bookcase. These cases can.
Flir One: Thermal vision

As the Predator and other aliens can attest, there’s a hidden universe lurking just beyond the visible spectrum. The $349 Flir One is a case for the iPhone 5 that lets you view the world as varying shades of hot and cold rather than in a spectrum of ordinary colors.
The first question you might ask is: Why on earth would you need such a thing? Actually, infrared thermal imaging has a lot of applications, ranging from household repair and DIY projects to wildlife hunting to, well, ghost hunting. And since thermal imagers are generally quite expensive (starting around $1000), the Flir One turns your iPhone into a bargain priced IR imager.
The case is a bulky sled that doubles the thickness of your iPhone 5, and since it does not do double-duty as a charger, you probably won’t want to leave it attached all the time. You can leave the companion sleeve on your iPhone, though. The back of the case has side-by-side infrared and visible light sensors. They work together to give you a remarkably sharp thermal image—the two images are blended so it’s easier to see edges and details in the scene. That innovation makes it easy to understand what you’re looking at, something that’s not always true when looking at ordinary thermal images taken with a standalone IR sensor.

In operation, the Flir is both fun and functional, and works with a suite of five apps. There’s a general purpose Flir One app for shooting stills or video, as well as an app for shooting infrared panoramas, thermal-infused time-lapse video, and macro close-ups (with a manual adjustment for correcting the parallax between the two sensors). There’s also a somewhat more whimsical Paint app, which lets you selectively finger-paint a scene using color data from its real heat map. Flir also allows third parties to develop their own apps for the imager.
And don’t let the Paint app fool you; The Flir One is a powerful tool that puts infrared imaging in your hands at a discount price. A spot meter identifies the precise temperature in the crosshairs (accurate to within about three degrees), and a number of color modes let you see a rainbow heat map, or highlight just the hottest or coldest parts of a scene. You can use it to find heat loss in your home, “see into” plumbing to find blockages, hunt for vampire electrical sources, and even play doctor by looking at temperature asymmetries in someone’s body. I used the case to explore the hottest parts of my cat (it’s the ears and nose), see which electronics around the house run hot even when in standby mode, and spotted where my dog had an “accident” on the carpet. Of course, that’s just scratching the surface; a true DIY-er could find all sorts of uses for the Flir. You could even use it, presumably, to find the freshest bread at the grocery store.
TaskOne: Hardware utility
The $99 TaskOne is like an iPhone case with a Swiss Army knife built in. And that’s not hyperbole: It really has a knife, a 2.5-inch long sawblade with serrated edge, to be precise. You could literally cut wood with your iPhone, if you were so inclined. But I’m getting ahead of myself.

The TaskOne is a bumper-style case with a half-dozen integrated tools for MacGyvers who never know when they’ll need a screwdriver. The case is actually quite rigid, and encloses securely around the phone with the help of four tiny screws and an Allen wrench—this is not a case you’ll casually slip on and off as the mood strikes you.
There are recesses and cutouts for all the controls and ports, as you’d expect, but it’s the back of the case that’s the most interesting. There, you’ll find four low-profile sliders that push a handful of tools out of various sides of the case. You can slide out a pair of screwdrivers—small and medium flatheads, with a low-profile Philips head to boot. The Allen wrench tool has a half dozen wrench sizes, a pair of bike spoke wrenches, and a rudimentary wire cutter. There’s even a pair of pliers—it’s permanently integrated into the case, but thoroughly functional—and a non-removable can opener. Perhaps the most unusual feature, though, is the knife. It’s quite sharp, and slides out of the case a full 2.5 inches. Plus, the rigid nature of the case means you can actually use your phone as the knife grip.
Of course, the TSA might have some concerns about traveling with a knife embedded in your phone, so you can pop the blade out and leave it home when you travel‚and I’d recommend not forgetting that step before you head to the airport.
The TaskOne is one of the more curious iPhone accessories, and it’s a great find for dedicated outdoorsmen and DIY-ers. I found the tools a little small and clumsy for routine use; the Allen wrench, for example, is a pain to use, and the pliers can be hard to keep a grip on given their modest 3/4-inch throw. The case is solidly constructed though, and should keep your iPhone safe…unless you unwisely also choose to use the TaskOne as a hammer.