Is Linkage compatible with Apple iPad?
No, the Linkage application ins't compatible with the iPad and its operating system. The only download available on their official website is for the Windows operating system. Currently, there are no emulators to run a Windows app on an iPad device.
If you want to know when will Linkage be available for Apple iPad, get in touch with developers.
There will likely never be an iPad version of this software. Although there is an open-source version available, it would be a daunting task to convert the software source code to run on iOS. I, the original developer, have no plan to do that work.