Well, if you're targeting mobile, and by 'mobile' you include Android, you already have to use Java. You could use Clojure in this case as well, but Clojure in my experience is too inconvenient on Android to be worth it (yet.)
I think he is just referring to iOS. However I have to disagree the author that it's suitable for desktop GUI applications. I hate running Java programs on desktops (may be except Eclipse), as they always take much more resources than they actually needs, while still maintaining ugly interfaces all over different platforms, or would require much more work for the developers to solve issues with incompatibilities over different configurations of Java installs. For GUIs, Java is _still_ (for since Swing was available) not the choice.
What did you dislike about it? App scaffolding? Compiling? Deployment? Use of Java libraries inside Clojure?
The other issue I ran into was that there were issues in getting Clojure to interact with Android properly. Android requires that you compile your code into classes which means you will have to use :genclass in Clojure and implement a lot of interfaces. This in itself isn't that much of a problem (it will make you code less Lispy but oh well) but when I tried it there were bugs in Clojure which made it impossible for me to do some things on Android that I would have liked. That part of the language runtime is a little immature in my experience.
I wouldn't give up based on my words though. It may have improved since I last tried. If you want to look someplace for info on how to get started, I found that this fellow has a lot to offer: http://www.deepbluelambda.org/programming/clojure/creating-a...
I've seen toy Clojure apps running on Android 2.2 and they took sensibly less than 5-10 seconds to load. I'm mentioning this since parent doesn't specify which Android version he was using, and JIT compiling was only recently introduced in 2.2.