Official Sony Xperia Xz So-01j -docomo Japan- Stock Rom May 2026

For more advanced flashing (only if official tools fail):

Despite the bloat, the official Stock ROM offered functionalities that made international users jealous. The ROM was coded specifically to leverage the Japanese market's infrastructure in ways Google’s stock Android could not.

If you are using the phone on Docomo’s network (or an MVNO like IIJmio or Rakuten Mobile), the stock ROM ensures VoLTE (Voice over LTE), Wi-Fi calling, and visual voicemail work correctly. These features almost never work on generic or custom firmwares. Official Sony Xperia XZ SO-01J -Docomo Japan- Stock Rom

Bootloader Status – Locked bootloader recommended for guaranteed OTA updates. Unlocked may still work but could break some carrier features.

Docomo Bloatware – Stock ROM includes Japanese carrier apps (dメニュー, dアカウント, etc.). These can be disabled, not easily removed without root.