First Android M Upgrade ASUS Phone Models:

ASUS PadFoneS (PF500KL)

ASUS ZenFone2 (ZE550ML/ZE551ML)

ASUS ZenFone2 Deluxe / Special Edition (ZE551ML)

ASUS ZenFone2 Laser(ZE500KG/ZE500KL/ZE550KL/ZE600KL/ZE601KL)

ASUS ZenFone Selfie (ZD551KL)

Though ASUS Official has released its specific model list, the specific Android M launch date is still unknown, please stay tuned for our later reports. Once we got the ASUS latet Android 6.0 M firmware, we will release it on our website at the first time.

Source from: http://www.androidmall.co.uk/blog/asus-mobile-releaed-android-6-0-firmware-update-list/