Introduction to Android 9
Android 9, known as Android Pie, was officially announced by Google on August 6, 2018. This major release brought numerous features and updates designed to enhance user experience, improve performance, and boost security.
History of Development
Development began with the first developer preview on March 7, 2018. Subsequent previews and betas followed, with the final beta released on July 25, 2018. Extensive testing and user feedback helped refine features and address bugs.
Key Features of Android 9
Adaptive Battery
Adaptive Battery uses machine learning to identify frequently used apps, adjusting battery usage accordingly. This prioritizes active apps and delays notifications for less frequently used ones.
Adaptive Brightness
Adaptive Brightness automatically adjusts screen brightness based on detected lighting conditions, ensuring optimal visibility in varying environments.
Gesture Navigation
A new gesture navigation system replaces the traditional three-button setup. Users can swipe up from the center to go home, swipe from the sides to go back, and swipe from the bottom edge to open the app switcher.
App Actions and Slices
App Actions and Slices make it easier to perform tasks directly from the home screen or search bar. For instance, tapping a food-delivery app may show the last restaurant ordered from, speeding up re-orders.
Digital Wellbeing
Digital Wellbeing helps users manage screen time by tracking app interactions, device checks, and notifications. This data helps identify time-sinking apps and reduce usage.
Security Enhancements
Several security enhancements protect user data. Notably, access to mic, camera, and SensorManager sensors is restricted for idle apps, ensuring they cannot use these features when not in use.
Private DNS
Support for DNS over TLS, known as Private DNS, enhances privacy by encrypting DNS queries, making it harder for third parties to intercept and manipulate internet traffic.
External Camera Support
Android 9 supports external USB/UVC cameras on certain devices, opening new possibilities for camera applications, including depth, bokeh, and stereo vision.
Accessibility Features
Several accessibility features make the operating system more usable for people with disabilities. These include an Accessibility Menu for common actions like taking screenshots and Select to Speak, which reads aloud selected text.
Custom Distributions and Compatibility
While the official release was limited to specific devices, several custom distributions (ROMs) were developed by the community, often including additional features and tweaks. Updates to the Compatibility Definition Document (CDD) ensured devices met certain standards for compatibility.
Enterprise Features
Several enterprise-focused features improve device management and security in corporate environments. One notable feature is the ability to pause OTA updates indefinitely, including security updates, useful for controlled update management.
Performance Enhancements
APK Caching Solution
An APK caching solution allows rapid installation of preloaded apps on devices supporting A/B partitions. This feature places preloads and popular apps in the APK cache stored mostly in the empty B partition without impacting user-facing data space.
Profile-Guided Optimization
Support for Clang's profile-guided optimization (PGO) on native Android modules helps optimize code for better performance.
Write-Ahead Logging
Compatibility write-ahead logging (WAL) in SQLiteDatabase allows a database to use journal_mode=WAL while keeping a maximum of one connection per database, enhancing performance by reducing transaction time.
Power Management
Background Restrictions
Users can restrict apps that may drain battery power. The system may also suggest disabling apps negatively affecting device health.
Batteryless Devices
Android 9 handles batteryless devices more elegantly, removing code that assumed a battery was present, charged at 100%, and in good health with a normal temperature reading on its thermistor.
Display and Graphics
Display Cutouts
App developers can create immersive, edge-to-edge experiences while allowing space for important sensors on the front of devices.
Rotate Suggestions
Updates to screen rotation behavior include support for a user-facing control to pin screen rotation to either landscape or portrait even if the device position changes.
Synchronized App Transitions
Synchronized app transitions allow for new app transition animations, enhancing the visual appeal of the operating system.
Wide-Gamut Color
Support for wide-gamut color, including high dynamic range (HDR) and processing content in the BT2020 color space, requires a device’s full display stack to support wide-gamut colors or buffer formats.
Rollout and Compatibility
The rollout began with Google Pixel devices and later extended to other devices. The Essential Phone was the first third-party device to receive the update, followed by the Sony Xperia XZ3, which came with Android Pie pre-installed.
Samsung started with beta testing for the Galaxy Note 9 in December 2018, later releasing the stable version of Android Pie with One UI for the Galaxy S9 and S9 Plus. The rollout continued with other Samsung devices, including the Galaxy A7, A8, A8 Plus, and A9 (2018), which received the update between April and October 2019.
Reception and Impact
Initial reception was mixed. Some users on Pixel devices and the Essential Phone noted a decrease in battery life shortly after the launch. However, as more devices received the update, similar comparisons were reported by users on various devices.
Despite initial issues, Android 9 has significantly impacted the mobile industry. Gesture navigation and adaptive battery features have set new standards for future releases. Emphasis on security and privacy has been well-received by users and developers alike.
Android 9, or Android Pie, marked a significant milestone in the evolution of the Android operating system. With its focus on user experience, performance, and security, it has set the stage for future releases. The gradual rollout and compatibility with various devices have ensured that a wide range of users can benefit from its features. As technology continues to advance, it will be interesting to see how future versions of Android build upon the foundation laid by Android 9.
