When comparing Moka vs Iris, the Slant community recommends Iris for most people. In the question“What are the best gtk3 themes?” Iris is ranked 10th while Moka is ranked 15th. 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 Several distro specific instruction to download
Moka offers suers easy to follow instructions to download including PPA's for Ubuntu based distros and Fedora specific instructions to install its repo.
Pro Wide support
Besides this Gnome Shell theme there are multiple GTK and icon themes that match, giving the user a wide variety of themes to mix and match that still look great together.
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 Does not work on older version of Gnome Shell
Moka does not work on Ubuntu 12.04 nor will it work on Debian Wheezy as they both use old version of Gnome Shell.