When comparing Zukitwo vs Iris, the Slant community recommends Iris for most people. In the question“What are the best gtk3 themes?” Iris is ranked 10th while Zukitwo is ranked 16th. The most important reason people chose Iris is:
Iris has filters that can be purchased through in app purchases that allow for increased visibility in certain lighting situations.
Ranked in these QuestionsQuestion Ranking
Pros
Pro Built in matching GTK theme
Zukitwo theme offers a matching GTK theme to the built in Gnome Shell theme.
Pro Offers PPA for easy install on Ubuntu based distros
Zukitwo offers an Ubuntu PPA for Ubuntu based distros.
sudo add-apt-repository ppa:noobslab/themes
sudo apt-get update
sudo apt-get install zukitwo
Pro Purchasable filters to heighten visibility in certain conditions
Iris has filters that can be purchased through in app purchases that allow for increased visibility in certain lighting situations.
Pro Easily turned on and off
Iris has a quick toggle in the notification drawer with allows for the user to easily turn on and off the function of the app.
Pro Puts an overlay of your camera feed on top of all other apps
By overlaying what the camera sees over any app on the device, users can see what is in front of them while still looking at their screen, retaining all the functionality of every app or game they use.
Cons
Con Only supports latest version of Gnome Shell and GTK
Zukitwo only officially supports the latest release of Gnome Shell and GTK.