Developer Preview 2 came out on 17 May 2017, at Google I/O. Google called it “our first beta-quality candidate, available to test on your primary phone or tablet”, and opened the Android Beta program to Android O the same day.
| Release date | 17 May 2017 |
| Build | OPP2.170420.017 |
| Devices | Nexus 5X, Nexus 6P, Nexus Player, Pixel, Pixel XL and Pixel C; emulator |
| How to get it | Over the air through Android Beta, or by flashing the factory image |
| Platform stability | No; APIs changed since Preview 1, and Google pointed to the API diff report |
What Preview 2 added
- Notification dots on launcher icons, which Google said “work with zero effort for most apps”, with the dot colour taken from the icon.
- Autofill with Google, Chrome’s autofill brought to Android apps on top of the autofill framework. Apps can give hints about the data a field expects.
- Smart Text Selection: on-device machine learning selects a whole address, URL, phone number or email address and offers the matching app.
- A new Android TV home screen where apps publish channels, through the
TvProvidersupport library.
Google also announced TensorFlow Lite and a Neural Networks API for a maintenance update later that year, and showed Android Go for devices with 1 GB of memory or less.
The support libraries moved from the SDK Manager to Google’s Maven repository with Support Library 26.0.0 beta. Devices enrolled in the Android N beta had to enroll again to receive O, 9to5Google reported.