I have been getting many question on how to downgrade Asus ZenFone Max Plus (M1) from Android 9 (Pie) back to Android 8 (Oreo). This is a very highly requested feature in the forums. Asus released unfinished Oreo version of the firmware, and then after a long time tried to fix it with a beta of Android Pie firmware. This made things only worse so many users want to downgrade from Android 9 back to Android 8.
The official firmware site offers the firmware and instructions how to achieve that. The process will downgrade the Max Plus to version WW-15.02.1904.453, which was the latest Oreo 8.1.0. version offered for this phone.
Here is the process in full:
Version Android P downgrade to O
ASUS ZenFone Max Plus(M1) Software downgrade to target Image Version: WW-15.02.1904.453 (Android 8.1.0 Oreo) by using MicroSD card for WW SKU only* Please follow step 6 and ensure to backup data before downgrade.
Steps of Update:
1. Prepare a MicroSD card.
2. Check software version of your device**
3. Only apply to same SKU update, Example: WW->WW, CN->CN, TW->TW, ID->ID.
4. Software update cannot transfer the software SKU.
5. Wrong SKU may cause update failure, please update the same SKU version only.
6. How to manual update firmware please refer to
On the link provided you can read step by step instructions with photos.
Please note that this process will erase (delete) all data on your phone, so make a backup first (at least photos and videos, but also app settings and apps itself if they are not available any more).
Since it’s possible and fairly easy to downgrade from Android 9 to Android 8, many users would prefer to downgrade from Android 8 to Android 7. Yes, Android 7 firmware wasn’t perfect, but by many means better than Android 8 implementation for ZenFone Max Plus. Sadly, Asus hasn’t offered a way to downgrade, so all there is are the unofficial ways to achieve that.