The version 2.2.0 of the Jailbreak tool was released few hours after iOS 8.4 was announced after the developers confirmed that Apple didn’t patch the vulnerabilities in iOS 8.3.
Before you can use the tool to jailbreak your iOS device, you are required to have upgraded to at least iOS 8.3 because Apple had patched several vulnerabilities used by the TaiG and PPJailbreak in iOS 8.1.3, and also patch another vulnerabilities in iOS 8.2.
Before you start, please take a backup of your device, preferably using iTunes. Temporarily Disable Passcode from Settings > Touch ID & Passcode and also temporarily turn off Find my iPhone from Settings > iCloud > Find my iPhone.
You can check out the updated step by step jailbreak guide on TaiG website.
You can also follow this guide.
Once completed, launch the Cydia app to find and install jailbreak apps and tweaks.
ifile, pandora downloader, kodi.appcake are some of the tweaks that have been reported to be working after making use of the TaiG v2.2.0 jailbreak tool.
I hope it works for you.