Is ANDROID_ID still unreliable in 2013 / 4.x?

Question

I've seen the reports on the internet about duplicate android ids (eg. Is there a unique Android device ID? ). They're mostly from 2010, with a couple of updates saying it was still broken in 2011. But what's happened since then? Are there still a lot of devices out there with duplicate IDs, or did OS updates fix them?

(side note: yes, there are other options, like the serial number and telephony id, but there are also reports of those values being unreliable.)

I only need to support 4.0+ (api 15), so if the problem is guaranteed to be fixed there I will be very happy. :)

UPDATE: I found https://code.google.com/p/android/issues/detail?id=10639 which strongly suggests that devices shipped with >=2.3 are fine, but what about devices shipped with 2.2 and then upgraded? And what about the reports that phones were still broken in 2011 - possibly after 2.3 was released? I hope that those reports were just un-upgraded phones, but I want to be sure.

Answer 1

It is not unreliable per se, the bug that plauged 2.2 is no more.

However:

• The ANDROID_ID is still dependant on the serial number and on the manufacturer following standards.

• There are a lot of cheap manufacturers that forego the necessary processes and as such ship devices (with 4.x) with identical serial numbers and android_ids. Ref: Same serial number on several android devices. Adb is useless. How can I change the serial number?

• Google notes there is at least one major provider (idk which) that also had this issue post 2.2

In short, it is reliable, but there will be still some minor instances where you will have issues, specially with cheap devices.