This may not come as a surprise, given that the phone boasts what Amazon calls Dynamic Perspective—the result of four low-power special cameras, four infrared LEDs, a dedicated processor, real-time computer-vision algorithms and a high-performing graphics-rendering engine.
Or what iFixit's Miro Djuric calls "its wonderful juju magic."
Djuric gave the Fire a paltry 3 out of a possible 10 on iFixit's repairability scale. While the teardown started out promisingly, with the discovery that Amazon used a "similar opening procedure" to the current iPhones and Torx T3 screws, instead of proprietary screws like Apple does, from there things went south.
Amazon's "fancy tech," wrote Djuric, "made for a veritable mess of cables, connectors and glue."
With a close-up look at the Dynamic Perspective's four IR projectors (one in each corner of the phone) and four IR cameras (also in the corners and "glued solidly in place"), Djuric offered an explanation of how the Fire—like some Samsung phones—can respond to where a user's eyes are on the display, or let a user control the phone, such as in a game, by moving her head.
The projectors are "blasting you with invisible (to the human eye) infrared rays any time you're staring at the phone while the display is on," he wrote. "The Fire Phone 'rectangulates' your position, figures out that there's a human face looking at the display, and stars doing its [juju]—all in real time."
Another notable finding, amid the glue, was a WCN3680 chipset that Djuric said supports Bluetooth LE 4.0—a technology that Amazon has said it will eventually support.
"Until then, any BLE [Bluetooth low energy] devices, such as the current slate of smart watches, are incompatible with the Fire Phone," he added.
Under iFixit's spudgers and suction cups, the Apple iPhone 5S has scored a 6 out of 10, with the team liking that its assembly is just like that of the iPhone 5 (which scored a 7) and so simplifies screen replacements. Plus, its battery is fairly easy to access (though not exactly easy to replace).
Apple's iPads, however, tend to evoke the fury of Djuric and his crew, who offer manuals to help people repair and reuse just about anything. The iPad Air, for example, which was essentially stuffed with glue, scored a 2 out of 10.
The Moto X, which the teardown team found to look as "fresh" inside as out, scored a 7.