I'd like to switch from using MP3 encoded audio files to AAC+ for voice sound files stored inside an Android app. This will make the install size smaller.
A problem I encountered is that AAC+ support was broken in the Froyo release of Android: http://code.google.com/p/android/issues/detail?id=9308
It was later fixed: https://android.googlesource.com/platform/frameworks/base/+/16263d9f8cc01392c2f3678b381ce897647c8c81
The Pandora FAQ apparently confirmed some phones were updated over the air, but warned about other phones:
Why am I experiencing audio issues on Froyo?
If you have upgraded to Froyo (Android 2.2), you may notice audio-quality issues while listening to Pandora. The Android team is aware of this issue with AAC+ audio and has released a fix, which is gradually being rolled out on the various Android handsets.
Currently the Sprint HTC EVO and the Google Nexus One have OTA Android OS updates that incorporate this AAC+ audio fix.
If you have a different handset than the two mentioned, please contact the support team for your handset if you have any further questions about this issue.
Have all Froyo phones been updated to include this fix? Or are there some carriers/manufacturers not bothering? Such is very common with Android, as they claim testing updates is too expensive.
My Flurry metrics are showing Android 2.2 at 33.2%, 2.2.1 at 12.2%, 2.2.2 at 0.1%. So if the fix only came with a version number change, it isn't out to most Froyo phones.
Based on the time of that commit, it was probably fixed in 2.2.1. Since there is no SDK level change in 2.2.1/2.2.2, Google doesn't track its usage separately from 2.2. Gingerbread and Honeycomb make up 19.5% of total installs as of July 5, 2011, and they all have the AAC+ fix for sure. Most manufacturers and carriers don't release any updates other than major ones (OS upgrades), so I would estimate that approximately 25% of all devices have this fix. You could also try using Ogg Vorbis, as support for it is built into all versions and the voice profile may be sufficient for what you plan on using it for.