title: In Android Studio which SDK platform tools to install?
body: <p>My SDK Manager shows two platform tools, one which comes under the folder 'Tools' which has revision 22, and the other which comes under the folder 'Tools (Preview Channel)' which has revision 23rc2. When I download and install one, after rebooting the SDK Manager, the other one comes as not installed and vice-versa. </p>
  
  <p><img src="https://i.stack.imgur.com/04Xhw.png" alt="enter image description here"></p>
  
  <p>So if only one can be installed which one should I go for?</p>