Samsung barely tweaked the exterior design of the Galaxy S4. That plastic casing might not be much to look at, but as iFixit's teardown reveals, that's precisely why you can replace much of its guts without any hassle.
The slim, aluminum unibody design of gorgeous handsets like the HTC One and the iPhone pose a real problem for DIY fixers. Those phones are sealed together so tightly, and their guts are packed so densely, that even with proper tools and some know-how, you might break something.
Getting at the Galaxy S4's guts, on the other hand, is a cinch. That's partly by design: The back cover pops off so you can replace the battery without any tools at all. From there, taking everything else apart by removing just 11 Phillips #0 screws.
Here's a look at the front side of the motherboard which shows off the Qualcomm 4G GSM/UMTS/LTE modem (red) and the Samsung 2GB LPDDR3 RAM (green) (The Qualcomm Snapdragon 600 1.9 GHz CPU is hiding behind the memory unit).
On the back of the mother board we're looking at some neat stuff like the Qualcomm seven-band 4G LTE chip (orange) and theBroadcom NFC chip (green). (There's more detail about the other components in these images as well as beautiful porn of all of other guts like the camera, in iFixit's teardown.)
Once you get to guts though, the surgery gets a little more complicated. The internal components are modular so you can replace them individually, but they're glued into place so you'll need to work a little to spring them loose. And you better not break the glass panel because it's permanently attached top both the AMOLED display and the phone's frame. But overall, if you've got the will to repair, iFixits guide will get you through it, which is more than you can about other phones out there. [iFixit]