1 <html devsite> 2 <head> 3 <title>Compatibility Program Overview</title> 4 <meta name="project_path" value="/_project.yaml" /> 5 <meta name="book_path" value="/_book.yaml" /> 6 </head> 7 <body> 8 <!-- 9 Copyright 2017 The Android Open Source Project 10 11 Licensed under the Apache License, Version 2.0 (the "License"); 12 you may not use this file except in compliance with the License. 13 You may obtain a copy of the License at 14 15 http://www.apache.org/licenses/LICENSE-2.0 16 17 Unless required by applicable law or agreed to in writing, software 18 distributed under the License is distributed on an "AS IS" BASIS, 19 WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 20 See the License for the specific language governing permissions and 21 limitations under the License. 22 --> 23 24 25 26 <p>The Android compatibility program makes it easy for mobile device 27 manufacturers to develop compatible Android devices.</p> 28 29 <h2 id="program-goals">Program goals</h2> 30 31 <p>The Android compatibility program works for the benefit of the entire 32 Android community, including users, developers, and device manufacturers.</p> 33 <p>Each group depends on the others. Users want a wide selection of devices 34 and great apps; great apps come from developers motivated by a large market 35 for their apps with many devices in users' hands; device manufacturers rely 36 on a wide variety of great apps to increase their products' value for 37 consumers.</p> 38 <p>Our goals were designed to benefit each of these groups:</p> 39 <ul> 40 <li> 41 <p><em>Provide a consistent application and hardware environment to application 42 developers.</em> 43 Without a strong compatibility standard, devices can vary so 44 greatly that developers must design different versions of their applications 45 for different devices. The compatibility program provides a precise definition 46 of what developers can expect from a compatible device in terms of APIs and 47 capabilities. Developers can use this information to make good design 48 decisions, and be confident that their apps will run well on any compatible 49 device.</p> 50 </li> 51 <li> 52 <p><em>Enable a consistent application experience for consumers.</em> 53 If an application runs well on one compatible Android device, it should run well on 54 any other device that is compatible with the same Android platform version. 55 Android devices will differ in hardware and software capabilities, so the 56 compatibility program also provides the tools needed for distribution systems 57 such as Google Play to implement appropriate filtering. This means 58 users see only the applications they can actually run.</p> 59 </li> 60 <li> 61 <p><em>Enable device manufacturers to differentiate while being 62 compatible.</em> 63 The Android compatibility program focuses on the aspects of 64 Android relevant to running third-party applications, which allows device 65 manufacturers the flexibility to create unique devices that are nonetheless 66 compatible.</p> 67 </li> 68 <li> 69 <p><em>Minimize costs and overhead associated with compatibility.</em> 70 Ensuring compatibility should be easy and inexpensive to 71 device manufacturers. The testing tool is free, open source, and 72 available for <a href="cts/downloads.html">download</a>. 73 It is designed to be used for continuous self-testing 74 during the device development process to eliminate the cost of changing your 75 workflow or sending your device to a third party for testing. Meanwhile, there 76 are no required certifications, and thus no corresponding costs and 77 fees.</p> 78 </li> 79 </ul> 80 81 <h2 id="program-components">Program components</h2> 82 83 <p>The Android compatibility program consists of three key components:</p> 84 <ul> 85 <li>The <a href="https://android.googlesource.com/">Android Open Source Project</a> source code</li> 86 <li>The <a href="cdd.html">Compatilbility Definition Document (CDD)<a/>, representing the "policy" aspect of compatibility</li> 87 <li>The <a href="cts/index.html">Compatilbility Test Suite (CTS)</a>, representing the "mechanism" of compatibility</li> 88 </ul> 89 90 <p>Just as each version of the Android platform exists in a separate branch in 91 the source code tree, there is a separate CTS and CDD for each version as 92 well. The CDD, CTS, and source code are -- along with your hardware and your 93 software customizations -- everything you need to create a compatible device.</p> 94 95 </body> 96 </html> 97
