Nokia Lumia 520 Custom ROM Review: Breathing New Life into a Budget Classic
Installing a custom ROM on this device is possible, but it is a complex process. Unlike Android phones, Lumias require specialized tools to unlock the bootloader. Primary Goal: Most users install Windows 10 Mobile Hardware Limits: With only 512MB of RAM, performance will be slow.
Before diving in, it is crucial to understand the architecture. The Lumia 520 runs on a Qualcomm Snapdragon S4 Play (MSM8227). Unlike Android devices, where unlocking a bootloader is the first step to flashing a custom kernel, Windows Phone devices were heavily locked down by Microsoft and Nokia. Nokia Lumia 520 Custom Rom
Hard Bricks: Messing with the Qualcomm bootloader can easily render the device completely dead and unresponsive (often showing up as a QHSUSB_DLOAD error on a PC).
However, the hardware is surprisingly robust due to its root of trust exploits (Qualcomm’s "Emergency Download" mode). Thanks to developers on the XDA Developers Forums and Lumia WoA (Windows on ARM) project, we have three major categories of Custom ROMs available: Nokia Lumia 520 Custom ROM Review: Breathing New
Most development for this device (codenamed "fame") is hosted on platforms like XDA-Developers.
For this guide, I am installing Windows 10 Mobile (1511) because the 520 only has 512MB RAM – do not try newer builds! Unlock bootloader (requires old Nokia USB protocol, risky)
Limitations and risks