Put simply, FlipLaunch adds 'Quick App Launch' shortcuts to any tweak that uses the toggle framework, FlipSwitch.
To use FlipLaunch, you'll need to go to FlipLaunch's preferences, enable an app you wish to use, then simply enable that new shortcut in any FlipSwitch enabled tweak.
Source code available on Github
Configure options from Settings.
Screenshot shows Ryan Petrich's tweak, FlipControlCenter. Not yet available.