How to Install Custom Android ROM

I purchased a Redmi K30 from China, and it did not come with Google services. I attempted to install Google services from a third-party source, but it was missing some essential components, such as parental controls. Consequently, I decided to install an EU ROM.

The process was rather intricate, so I've documented the procedures here in case they might be helpful.

background knowledge

• there are 2 partitions in your phone

  • recovery partition: contain tools to install the android os
  • system partition: where the android os resides

• TWRP: a 3rd party recovery tool

  • can override the stock recovery program
  • allow you to install 3rd party android ROM, eg. EU ROM
  • optionally install to the recovery partition, replace the stock recovery program

• fastboot mode

  • enter by long press volume down and power button
  • for unlock the phone, flash recovery partition... etc

• fastboot tools

  • program to flash the recovery partition with TWRP
  • or directly run TWRP without flashing the original recovery partition

• fastboot mode ≠ fastboot tools

tools download

• First thing first: check the code name of your phone eg. Redmi K30 = phoenix
• xiaomi phone unlock tool + pc driver (pc only) https://en.miui.com/unlock/download_en.html
• fastboot tools (mac/pc) https://provider.xiaomi.eu/tools/fastboot.zip
• TWRP (recovery image, model specific) https://bit.ly/3ZITelV
• EU MIUI rom (model specific) https://bit.ly/45fMmNU

unlock the phone (pc only)

• enable dev mode on the phone
  • enable OEM unlocking and USB debugging
• install phone driver on PC
• apply phone unlock from xiaomi, using the unlock tool
• ⚠️ wait 7 days ⚠️
  • don't press apply again within 7 days otherwise it will reset the waiting time‼️
• after 7 days, unlock the phone
  • boot into fastboot mode (long press volume down & power button)
  • unlock with the xiaomi unlock tool

run TWRP (mac/pc)

• boot the phone to fastboot mode (volume down + power) and connect to computer
• rename the TWRP image to recovery.img and put it in the same folder with fastboot binary

• in terminal, run fastboot boot recovery.img

• (optional) flash the recovery partition with TWRP

  • do if you want to replace the stock recovery program for good
  • easier to re-install or change the android os in future

• copy the EU rom to phone's root directory

  • you may not see the phone in computer before boot to TWRP
  • mac: use android file transfer
  • pc: use file manager
  • disconnect phone from computer

install custom ROM

• in TWRP home, press install
• select the rom image(zip file), slide to install
• press wipe cache
• back several times to TWRP home
• press wipe > format data

• press reboot system (if no response after 3mins, press power button to reboot)

• done 🎉

questions?

• my twitter
• github profile