Is there a way for it to work? 
Howdy Mikiro,
Thank you for reporting this issue. We are aware of Zen garden only working on a select number of devices. The reason behind that is that Zen Garden need to be on a device that will be able to support iOS metal. The iTunes store is allowing the app to be downloaded on devices that is may not be compatible with. At this time, There is only a hand full of devices that have the processor capable of running Metal for iOS.
Thanks and have a great day!