pdk/docs/compatibility/index.jd

page.title=Android Compatibility
doc.type=compatibility
@jd:body
<p>Android is an open source product, and anyone can use the source code to build
devices. The purpose of the Android compatibility program is to help Android
device implementations remain compatible with all apps.</p>
<p>A device is considered compatible if existing and new third-party
applications run correctly on it. Poor device implementations that change APIs
or alter behaviors will break these apps and so are not compatible. The
Android compatibility program's aim is to ensure that these APIs are
consistently implemented across devices.</p>
<p>The latest version of the Android source code and compatibility program is
1.6, which roughly corresponded to the Donut branch.  The compatibility
program for Android 2.x (corresponding to Eclair) is coming soon.</p>
<h2>Why build compatible Android devices?</h2>
<h3>Users want a customizable device.</h3>
<p>A mobile phone is a highly personal, always-on, always-present gateway to
the Internet. We haven't met a user yet who didn't want to customize it by
extending its functionality. That's why Android was designed as a robust
platform for running after-market applications.</p>

<h3>Developers outnumber us all.</h3>
<p>No device manufacturer can hope to write all the software that anyone could
conceivably need. We need third-party developers to write the apps users want,
so the Android Open Source Project aims to make it as easy and open as
possible for developers to build apps.</p>

<h3>Everyone needs a common ecosystem.</h3>
<p>Every line of code developers write to work around a particular phone's bug
is a line of code that didn't add a new feature. The more compatible phones
there are, the more apps there will be. By building a fully compatible Android
device, you benefit from the huge pool of apps written for Android, while
increasing the incentive for developers to build more of those apps.</p>


<h2>Android compatibility is free, and it's easy.</h2>
<p>If you are building a mobile device, you can follow these steps to make
sure your device is compatible with Android. For more details about the
Android compatibility program in general, see <a
href="{@docRoot}compatibility/overview.html">the program overview</a>.</p>
<p>Building a compatible device is a four-step process:</p>
<ol>
  <li><b>Obtain the Android software stack source code</b><p>This is the
  <a href="{@docRoot}source/index.html">source code for the Android
  platform</a>, that you port to your hardware.</p></li>
  <li><b>Comply with Android Compatibility Definition Document</b><p>
  This document enumerates the software and the hardware features of
  a compatible Android device.</p></li>
  <li><b>Pass the Compatibility Test Suite (CTS)</b><p>You can use the CTS
  (included in the Android source code) as an ongoing aid to compatibility
  during the development process.</p></li>
  <li><b>Submit CTS report</b><p>[Optional] You can also submit your CTS report,
  so that it can be validated and recorded.</p><p><i>Note:
  the submission system is currently under construciton, and is not currently
  available.</i></p></li>
</ol>

<h2>Benefits of compatibility</h2>
<p>By submitting a validated CTS report, you receive public recognition of
your device's compatibility. This also opens up additional options you can
pursue such as use of the Android branding, access to Android Market, and
more.</p>
<p>As a consequence of some legal quirks, we aren't able to offer automatic
licensing of either the Android Market or branding. To actually obtain access
to these programs, you will need to <a
href="{@docRoot}compatibility/contact-us.html">contact us</a> to obtain a
license.</p>