Infrastructure - Architecture & Performance
- Android Vitals - More visibility in Google Play dev console on battery drain, wakelocks being held for too long, ANRs, crashes, dropped frames, and frozen frames.
- Architecture components - better handling of the lifecycle, Room (ORM for Sqlite), live data observers. The API looks clunky though.
Performance
- 50% 1-star reviews mention stability & bugs.
- 60% 5-star reviews mention speed, design, or reliability.
- Apps with > 5% crash rate have 30% higher uninstall rate.
Emerging Markets
- > 100M users came online in 2016.
- 1B 2G devices expected in 2020.
- 50% of India is on 2G
- 33% users run out of storage in India every day.
- Data is expensive - it costs ~$2 to download a 40MB free app in India
- 53% users abandon websites if it takes more than 3 seconds to load
Action items
- Remove barriers - app size, always online requirement
- Optimize for 2G speeds
- Build for intermittent connectivity - offline is not a bug, its a state for the users
- Provide better multilingual support
- Guide new users - Case study: minimalistic empty chrome screen is unwelcoming in India. Adding links to recent websites and news articles made it more welcoming.
Android Go
Rechristened versions of Android One, to be installed on all devices with less than 1GB RAM going forward. Consists of Lite apps. More visibility into data usage, and easy mobile top-ups.
- Youtube Go, and Play Go will support P2P video & file sharing.
- Chrome Data saver on by default. Related: “Save-Data” header
- 10MB per app download size goal
- Multi-lingual GBoard
- More severe limits on background
- DEX reordering to increase disk locality of the content
Slimming down app size
Installed size consists of download size, followed by unpacking, compilation & optimization phase. 20% downloads are canceled or fail if app size >= 100MB
Action items
- minification via proguard
- split-density apk, can be automated by Google Play if you are willing to hand them your key
- vector drawable (API 14+), this might increase CPU & RAM usage for complex drawable though
- Exclude sparse translations
- Downloadable fonts
- AAPT2 - dead version elimination, resource de-duplication, and smarter image cruncher
Misc
- Kotlin officially supported in Android. Recommended talk: Introduction to Kotlin
- App overlay not allowed on the system UI anymore
- Android Studio Apk Analyzer is proguard-aware
- Brotli compression for Google Play app updates
- Instant apps
New Features (only in Android O)
- WebView improvements - safe browsing support, multi-process, crashes + low-mem handling
- Auto-fill
- Fonts as first class resources
- Improved Media file access - ability to share big files like videos from one app to another without fully downloading them first.
- New Skia Renderer to cut down jank.
- Color management for different color spaces. Support for wide color Gamut. I would highly recommend watching Understanding Color talk.
- Even more rigorous clamp down on background processes & wake locks usage to save battery
- ART - use JIT profiling to relayout dex file reduces RAM & I/O, new concurrent Garbage Collector (using read barrier) to remove GC pauses, more code inlining, code relocation, class hierarchy analysis to optimistically decide when classes & methods can be assumed final, automated SIMD instruction generation.
- App icons - background & foreground layers from the app (with mask from the system)
- Notifications - Separated into 4 chunks - ongoing, people-to-people, general, and BTW. Notifications won’t reorder while you are looking at them. Notification Channels (notification categories which users can block/mute), mandatory for targeting API 26. App icon badging (“dot” in Google’ parlance).
New Features (backported via support library v26)
- Support library going API 14+ only. 1% users (~20M by Google’s count) are still on API 10.
- Downloadable fonts
- EmojiCompat for backward emoji support
- Better use of RenderThread to cut down on jank (frame drops)