Can I play music files stored on my mobile device using the CDJ-3000X?

Yes.
First, import music files to your mobile device using rekordbox for iOS/Android, then connect it to the CDJ-3000X using PRO DJ LINK to play the music files on the unit.

After downloading music files from a PC/Mac, or the cloud, to rekordbox for iOS/Android using the Mobile Library Sync or the Cloud Library Sync function, you can play them on the CDJ-3000X via PRO DJ LINK.  

Note: Downloading from the cloud is not possible while a PRO DJ LINK connection is active. 
Note: Tracks from streaming services can't be played from a mobile device. 
Note: When using the built-in Wi-Fi function on the CDJ-3000X, you can't make a PRO DJ LINK connection. But, when the CDJ-3000X is connected to a Wi-Fi router via an Ethernet cable and the Wi-Fi router is connected to a mobile device via Wi-Fi, you can make a PRO DJ LINK connection.

For information on how to connect rekordbox for iOS/Android to the CDJ-3000X, please refer to the following.

■rekordbox for iOS
For details, see [rekordbox.com].

■rekordbox for Android
For details, see [rekordbox.com].