1. The phone original firmware edition is00CN _1_ 35H. 2.Download thefirmware on Taiwan official website (address: http://www.sharpmobile.com.tw/%E6%9C%8D%E5%8B%99%E6%94%AF%E6%8F%B4-s2 3. Change file name of the firmware and copy it in the root directory of the phone.(SAT-135E-0-00WW-B02-update.zip→SAT-136E-0-00CN-B02-update.zip ) 4. Do not set password with the phone, and never put the phone screen to sleep in phone setting. 5. When the system prompts the messages of discovering new firmware automatically, you can click to confirm the upgrade. 6. Restart the phone, and Google service will be installed.