Apple has just released the first beta seed for iOS 8.4 just 5 days after releasing iOS 8.3. This release comes with a revamped music app and bug fixes. This seed, like many before it, has been released mainly to developers and devices registered to a developer account. We strongly recommend that you stay away from it if you are jailbroken, as there is not a jailbreak tool available as of yet.  

Hopefully this version did not patch more vulnerabilities that can be used to jailbreak your iDevices.