As is tradition, iFixit has obtained a new phone and torn it asunder in hopes of learning what makes it tick. The Nexus 5X is the latest phone on the iFixit disassembly table, and it turns out to be much more repairable than other phones. You won't need any weird tools and many of the components are simple to replace.
You should check out the full teardown, but there are some highlights. The rear cover of the 5X is easy to pop off, just like the 2013 Nexus 5. However, there's no adhesive holding it in place as there was in the Nexus 5. The rear panel has all the antennas attached and the battery is in plain view. There's some light adhesive holding the battery in, but replacing it shouldn't be a problem. Interestingly, the device has a Qualcomm SMB1358 Quick Charge 2.0 IC, even though it doesn't seem to support the standard QC2.0 implementation. How very mysterious.
The motherboard is secured with ten standard phillips screws, and modules like the camera and Nexus Imprint sensor connect to it with easily removable spring contacts. The display is still fused to the glass, as is common in smartphones these days, but overall the Nexus 5X looks like a very repairable device with a 7/10 score. By comparison, the Galaxy S6 got a 4 and the HTC One M9 got a 2.