Ubuntu Phone OTA-9 is bringing improved Bluetooth support via landing BlueZ 5, their browser can now download files of arbitrary file formats, user-interface improvements, better Ubuntu Scopes (including audio scopes), support for custom ringtones, and a lot of bug-fixing. Ubuntu Phone OTA-9 remains based off Ubuntu 15.04, this time the 15.04.3 framework. In the bug-fixing space there is said to be performance boosts.
The BQ and Meizu Ubuntu Phones along with the select supported Nexus models will be receiving Ubuntu Phone OTA-9 beginning this morning. More details on the Ubuntu Phone Over The Air 9 update can be found via the release notes.