0) Preparation
0.1) Backup your important data to PC
0.2) Ensure you are running
Wiko Fever Android 6 already (also/especially when your device is not wiko fever, but a clone). If you are not, please update to it, before continuing here (replace the preloader from the wiko rom with your stock one, then use 'firmware upgrade' mode in sp flashtool.
NEVER use 'format all + download')
Extra steps, if you are on blu life one x:
https://forum.xda-developers.com/showpost.php?p=76003104&postcount=81
0.3) Download “twrp_wiko_fever_oreo.img“:
[url]http://www.mediafire.com/file/e96x8ltlyka392e/twrp_wiko_fever_oreo.img[/URL]
0.4) Download “madOS_8.1.0_fever_2018xxyy.zip“
[url]https://www.facebook.com/MediatekAndroidDevelopers/[/URL]
0.5) Optional, Download “Google Apps (aka Gapps)“:
[url]http://opengapps.org/[/URL]. Choose: “ARM64“, “Android 8.1“, “nano“ or “pico“ package
1) Unlock bootloader (if not done already):
1.1) Boot for first time your device. I recommend to NOT register/login/add Wifi/add accounts/etc., because the unlock process DELETES all your data in the device. So to go more fast, skip all, and go directly to SETTINGS. In section ABOUT DEVICE, enable the developer options with eight time picks over “Build number”. Then in SETTINGS/DEVELOPER OPTIONS, enable the option “OEM unlocking” and “USB debugging” (if not enabled already), and choose to alollow usb debugging in the popping up window.
1.2) Boot the device in the BOOTLOADER mode (using ADB: "adb reboot-bootloader"). Execute in your computer the command “fastboot oem unlock”, say YES with “vol+” and “power” buttons. Then select reboot. This ERASES completely your device (factory restore), but the bootloader will be UNLOCKED! Two reboots needed.
2) Flash the recovery and boot to it. (choose option a) if you don't have another TWRP already installed, else choose b))
2.1a) Boot in the BOOTLOADER mode (using ADB: "adb reboot-bootloader").
Then execute command “fastboot flash boot twrp_wiko_fever_oreo.img”;
and then “fastboot reboot” (this is a trick to directly bring you to the newly flashed recovery. You can't boot up your current/stock rom at this point anymore).
2.1b) Boot to your current TWRP. Choose install --> image, and select “twrp_wiko_fever_oreo.img“. Then choose “recovery“ as the target. After few seconds, and succesful installation, hit “back“ several times, then go to “reboot --> recovery“
3) Install
3.0) Optional, but recommended: Go to "Wipe --> Advanced Wipe", click "Cache" and then "Repair or Change File system". Then select "Change File system" and choose "F2FS". Swipe to confirm.
Hit "back" three times (you can again choose a partition to change now). Choose "Data" and do as above.
Hit "back" several times, to get back to the main menu. Choose "Reboot --> Recovery".
3.1) While already in recovery (TWRP), connect your phone to pc, and copy “madOS_8.1.0_fever_2018xxyy.zip“ and the Google Apps to your phone.
3.2) Go to "Wipe", and directly slide the slider to the right.
3.3) Get back to main menu with the "back" button
3.4) Go to "Install" and hit “madOS_8.1.0_fever_2018xxyy.zip“, then uncheck all boxes and hit "Add more zips", now choose the Google Apps.
Confirm installation by swiping the slider to the right.
3.5) Reboot System