Just over a year ago, Google released its first Developer Preview of Android N, which later became known as version 7.0 Nougat. Today, the company has announced details of Android O, the next major version of its ubiquitous OS, and released its first preview for devs too.
As Google itself acknowledges, "it's early days" in the development of the new version; indeed, it took several months for it to begin rolling out Android 7.0 as a complete update ready for public consumption. We'll no doubt hear a lot more about Android O at Google's I/O developer conference in May, but it has already revealed numerous key features that will be part of the new version when it rolls out later this year.
Background limits: Building on the work we began in Nougat, Android O puts a big priority on improving a user's battery life and the device's interactive performance. To make this possible, we've put additional automatic limits on what apps can do in the background, in three main areas: implicit broadcasts, background services, and location updates. These changes will make it easier to create apps that have minimal impact on a user's device and battery. Background limits represent a significant change in Android, so we want every developer to get familiar with them. Check out the documentation on background execution limits and background location limits for details.
Notification channels: Android O also introduces notification channels, which are new app-defined categories for notification content. Channels let developers give users fine-grained control over different kinds of notifications — users can block or change the behavior of each channel individually, rather than managing all of the app's notifications together.
Notification channels let users control your app's notification categories
Android O also adds new visuals and grouping to notifications that make it easier for users to see what's going on when they have an incoming message or are glancing at the notification shade.
Autofill APIs: Android users already depend on a range of password managers to autofill login details and repetitive information, which makes setting up new apps or placing transactions easier. Now we are making this work more easily across the ecosystem by adding platform support for autofill. Users can select an autofill app, similar to the way they select a keyboard app. The autofill app stores and secures user data, such as addresses, user names, and even passwords. For apps that want to handle autofill, we're adding new APIs to implement an Autofill service.
PIP for handsets and new windowing features: Picture in Picture (PIP) display is now available on phones and tablets, so users can continue watching a video while they're answering a chat or hailing a car. Apps can put themselves in PiP mode from the resumed or a pausing state where the system supports it - and you can specify the aspect ratio and a set of custom interactions (such as play/pause). Other new windowing features include a new app overlay window for apps to use instead of system alert window, and multi-display support for launching an activity on a remote display.
Font resources in XML: Fonts are now a fully supported resource type in Android O. Apps can now use fonts in XML layouts as well as define font families in XML — declaring the font style and weight along with the font files.
Adaptive icons: To help you integrate better with the device UI, you can now create adaptive icons that the system displays in different shapes, based on a mask selected by the device. The system also animates interactions with the icons, and them in the launcher, shortcuts, Settings, sharing dialogs, and in the overview screen.
Wide-gamut color for apps: Android developers of imaging apps can now take advantage of new devices that have a wide-gamut color capable display. To display wide gamut images, apps will need to enable a flag in their manifest (per activity) and load bitmaps with an embedded wide color profile (AdobeRGB, Pro Photo RGB, DCI-P3, etc.).
Connectivity: For the ultimate in audio fidelity, Android O now also supports high-quality Bluetooth audio codecs such as LDAC codec. We're also adding new Wi-Fi features as well, like Wi-Fi Aware, previously known as Neighbor Awareness Networking (NAN). On devices with the appropriate hardware, apps and nearby devices can discover and communicate over Wi-Fi without an Internet access point. We're working with our hardware partners to bring Wi-Fi Aware technology to devices as soon as possible.
The Telecom framework is extending ConnectionService APIs to enable third party calling apps integrate with System UI and operate seamlessly with other audio apps. For instance, apps can have their calls displayed and controlled in different kinds of UIs such as car head units.
Keyboard navigation: With the advent of Google Play apps on Chrome OS and other large form factors, we're seeing a resurgence of keyboard navigation use within these apps. In Android O we focused on building a more reliable, predictable model for "arrow" and "tab" navigation that aids both developers and end users.
AAudio API for Pro Audio: AAudio is a new native API that's designed specifically for apps that require high-performance, low-latency audio. Apps using AAudio read and write data via streams. In the Developer Preview we're releasing an early version of this new API to get your feedback.
WebView enhancements: In Android Nougat we introduced an optional multiprocess mode for WebView that moved the handling of web content into an isolated process. In Android O, we're enabling multiprocess mode by default and adding an API to let your app handle errors and crashes, for enhanced security and improved app stability. As a further security measure, you can now opt in your app's WebView objects to verify URLs through Google Safe Browsing.
Java 8 Language APIs and runtime optimizations: Android now supports several new Java Language APIs, including the new java.time API. In addition, the Android Runtime is faster than ever before, with improvements of up to 2x on some application benchmarks.
Partner platform contributions: Hardware manufacturers and silicon partners have accelerated fixes and enhancements to the Android platform in the O release. For example, Sony has contributed more than 30 feature enhancements, including the LDAC codec, and 250 bug fixes to Android O.
Google has launched a new Android O Developer Preview site offering details on its planned timeline for development, behavior changes in the new version, and new APIs. It's also preparing to release a new canary version of Android Studio 2.4 with early support for features in the new edition of the OS.
Google's announcement of Android O comes despite the fact that its most recent major update to the OS has made little progress in rolling out to devices so far. According to its own latest figures, Android 7.x Nougat is currently installed on just 2.8% of active devices, almost seven months after 7.0 was originally released. It's currently preparing for the release of Android 7.1.2 in the next couple of weeks.
Source: Android Developers (Google)