Support for International Users

Utilities for localization

Pseudo-locales make it easier to test your app's localization.

Android 4.3 also includes new utilities and APIs for creating better RTL strings and testing your localized UIs. A new BidiFormatter class provides a simple API for wrapping Unicode strings, so that RTL-script data is displayed as intended in LTR-locale messages and vice-versa. To let you use this utility more broadly in your apps, the BidiFormatter API is also now available for earlier platform versions through the Support Package in the Android SDK.

To assist you with managing date formatting across locales, Android 4.3 includes a new getBestDateTimePattern() method that automatically generates the best possible localized form of a Unicode UTS date for a locale that you specify. It’s a convenient way to provide a more localized experience for your users.

To help you test your app more easily in other locales, Android 4.3 introduces pseudo-locales as a new developer option. Pseudo-locales simulate the language, script, and display characteristics associated with a locale or language group. Currently, you can test with a pseudo-locale for Accented English, which lets you see how your UI works with script accents and characters used in a variety of European languages.

Accessibility and UI Automation

Accessibility services can declare new capability attributes to describe what their services can do and what platform features they use. For example, they can declare the capability to filter key events, retrieve window content, enable explore-by-touch, or enable web accessibility features. In some cases, services must declare a capability attribute before they can access related platform features. The system uses the service’s capability attributes to generate an opt-in dialog for users, so they can see and agree to the capabilities before launch.

Building on the accessibility framework in Android 4.3, a new UI automation framework lets tests interact with the device’s UI by simulating user actions and introspecting the screen content. Through the UI automation framework you can perform basic operations, set rotation of the screen, generate input events, take screenshots, and much more. It’s a powerful way to automate testing in realistic user scenarios, including actions or sequences that span multiple apps.

Enterprise and Security

Wi-Fi configuration for WPA2-Enterprise networks

Android sandbox reinforced with SELinux

Android now uses SELinux, a mandatory access control (MAC) system in the Linux kernel to augment the UID based application sandbox. This protects the operating system against potential security vulnerabilities.

KeyChain enhancements

The KeyChain API now provides a method that allows applications to confirm that system-wide keys are bound to ahardware root of trust for the device. This provides a place to create or store private keys that cannot be exported off the device, even in the event of a root or kernel compromise.

Android Keystore Provider

Android 4.3 introduces a keystore provider and APIs that allow applications to create exclusive-use keys. Using the APIs, apps can create or store private keys that cannot be seen or used by other apps, and can be added to the keystore without any user interaction.

The keystore provider provides the same security benefits that the KeyChain API provides for system-wide credentials, such as binding credentials to a device. Private keys in the keystore cannot be exported off the device.

Restrict Setuid from Android Apps

The /system partition is now mounted nosuid for zygote-spawned processes, preventing Android applications from executing setuid programs. This reduces root attack surface and likelihood of potential security vulnerabilities.

New Ways to Analyze Performance

Systrace uses a new command syntax and lets you collect more types of profiling data.

Enhanced Systrace logging

Android 4.3 supports an enhanced version of theSystrace tool that’s easier to use and that gives you access to more types of information to profile the performance of your app. You can now collect trace data from hardware modules, kernel functions,Dalvik VM including garbage collection, resources loading, and more.

Android 4.3 also includes new Trace APIs that you can use in your apps to mark specific sections of code to trace using Systrace begin/end events. When the marked sections of code execute, the system writes the begin/end events to the trace log. There's minimal impact on the performance of your app, so timings reported give you an accurate view of what your app is doing.

You can visualize app-specific events in a timeline in the Systrace output file and analyze the events in the context of other kernel and user space trace data. Together with existing Systrace tags, custom app sections can give you new ways to understand the performance and behavior of your apps.

 

On-screen GPU profiling in Android 4.3.

On-screen GPU profiling

Android 4.3 adds new developer options to help you analyze your app’s performance and pinpoint rendering issues on any device or emulator.

In the Profile GPU rendering option you can now visualize your app’s effective framerate on-screen, while the app is running. You can choose to display profiling data as on-screen bar or line graphs, with colors indicating time spent creating drawing commands (blue), issuing the commands (orange), and waiting for the commands to complete (yellow). The system updates the on-screen graphs continuously, displaying a graph for each visible Activity, including the navigation bar and notification bar.

A green line highlights the 16ms threshold for rendering operations, so you can assess the your app’s effective framerate relative to a 60 fps goal (because 1/60th of a second equals roughly 16ms). If you see operations that cross the green line, you can analyze them further using Systrace and other tools.

On devices running Android 4.2 and higher, developer options are hidden by default. You can reveal them at any time by tapping 7 times on Settings > About phone > Build number on any compatible Android device.

StrictMode warning for file URIs

The latest addition to the StrictMode tool is a policy constraint that warns when your app exposes a file:// URI to the system or another app. In some cases the receiving app may not have access to the file:// URI path, so when sharing files between apps, a content:// URI should be used (with the appropriate permission). This new policy helps you catch and fix such cases. If you’re looking for a convenient way to store and expose files to other apps, try using theFileProvider content provider that’s available in the Support Library.

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