Because of having such as issue on IOS 8.3 version, Apple updated and move to the operation system to IOS 8.4. As per Apple this version is main achievement because in the future Apple is going to launch new stream service, and this version is the foundation.
So in 8.4 series Apple first launch beta1 version for Developer testing and now latest version is beta2. So in near future, we have more beta version under 8.4 series.
Once release beta versions, regular users not caring of it, because they know bet will not be available for regular work. However, this time regular users more interesting for beta version because of jailbreak possibilities.
IOS 8.4 jailbreak
Actually, IOS user is waiting long period for use Cydia in the latest version, but still we do not have any good response. IOS 8.1.2 is the last version which have jailbreak after that Apple updated their IOS version till 8.4 versions and still regular users not lucky to have use Cydia.
So IOS future is clear, and we will definitely have jailbreak on IOS 8.4 versions because already we have a good response for 8.4 jailbreak. The I0n1c has been identified Apple security holes in IOS 8.4 version, and he has jailbreak his IOS 8.4 beta1 installed iPhone6 Device.
However, we cannot trust i0n1c because in the previous, he has addressed same jailbreak possibilities on IOS 7.1.1 versions, but he was not released a jailbreak tool. The only advantage is there is a security hole on latest versions.
So with this encouragement other jailbreak tool Developers such as TaiG / PP jailbreak and Pangu8 will test latest security hole and definitely release jailbreak in future IOS version with include IOS 8.4 versions.
TaiG / PP and Pangu8 for IOS 8.4 Jailbreak
With these jailbreak teams, TaiG have more advantage for future IOS jailbreak because they already released IOS 8.2 beta1 and beta2 jailbreak. However, we cannot eliminate other Developers once TaiG release jailbreak for future IOS version PP definitely focuses for jailbreak release because PP is the only team which is the release jailbreak for Mac operation system.
Support IOS Devices
Still Apple not caring old Devices and this release also focus latest Devices and all IOS 8 select Devices also select for IOS 8.4 versions. In additionally, Apple added iWatch Device for IOS 8.4 versions.
Features of IOS 8.4 version
With IOS 8.4 version not much added new features, and only major feature is the new music app launch. However, Apple never goes to x.4 versions, and this is the first time. So 8.4 seem to be a big milestone of the Apple. As per Apple-related gossip news, near future Apple is going to launch new music stream service. So this would-be first foundation of it.
IOS 8.4 update warning
Still IOS 8.4 in beta versions and not to recommend to update once it arrives because we need some time to add our semi jailbreak function on to it. After semi jailbreak confirmations, IOS users can update Device version to 8.4 to take better advantage of the IOS Device.