When Mixvibes releases an update for Cross DJ Pro (adding new features or fixing bugs), the modded version becomes obsolete. You cannot simply update a modded app through the Google Play Store. You must wait for the modder to crack the new version,
If you need a free, open-source DJ app with no strings attached, try (via their official beta on Android). It is underpowered compared to Cross DJ, but it is 100% legal and malware-free. Cross Dj Pro On Modded.com