If you would like to restrict playback of your track, you can choose to disable app playback through your track's Permissions tab. This means that your track will only be playable on SoundCloud and through SoundCloud embeds, instead of websites or apps that use our API. 
 

You can disable or enable app playback through the track’s edit page in the ‘Permissions’ tab. You can access this edit page at any time through the pencil icon under it's waveform.