Which channel do I use in Flutter SDK? : <p>There was an announcement of Preview 1 at " 
<a href="https://medium.com/flutter-io/flutter-release-preview-1-943a9b6ee65a" rel="noreferrer">Announcing Flutter Release Preview 1 – Flutter – Medium</a>"</p>

<p>Download the latest beta release of the Flutter SDK In the document.
<a href="https://flutter.io/setup-macos/" rel="noreferrer">Get Started: Install on macOS - Flutter</a></p>

<p>Latest beta release version is 0.5.1. It's updated 2 months ago...</p>

<pre><code>$ flutter upgrade

Flutter 0.5.1 • channel beta • https://github.com/flutter/flutter.git
Framework • revision c7ea3ca377 (9 weeks ago) • 2018-05-29 21:07:33 +0200
Engine • revision 1ed25ca7b7
Tools • Dart 2.0.0-dev.58.0.flutter-f981f09760
</code></pre>

<p>Latest master release version is 0.5.8-pre.163.</p>

<pre><code>$ flutter channel master
$ flutter upgrade

Flutter 0.5.8-pre.163 • channel master • https://github.com/flutter/flutter.git
Framework • revision 29410abbe7 (2 days ago) • 2018-07-27 22:10:39 -0700
Engine • revision 72a38a6b13
Tools • Dart 2.0.0-dev.69.3.flutter-937ee2e8ca
</code></pre>

<p><strong>Which channel do I use in Flutter SDK?</strong></p>
