Hi there,
Thanks for writing and sorry for the delayed reply. Interestingly the file name you mentioned is the same as the native desktop forms designer, but you could be right that it is the one for the mobile device.
If you log in to our download site:
http://www.ddhsoftware.com/downloadyou should be able to see what desktop apps you've purchased. If any of them include the Professional or Enterprise name (you mentioned you have pro), you may already have the true forms designer. If you are up to date with HanDBase v4 of it (and it wasn't an old legacy version) you should be able to use the forms designer from your old PPC version just fine, as the format of the files it creates is the same. If it's v3, you'll be best to just purchase the Professional version for iPhone or Android (either will work for forms designing).
If indeed you need to purchase, the HanDBase Professional for iPhone/iPad add-on or the HanDBase Professional for Android Add-on would do the trick and give you syncing to your device as well- something you won't get with your PPC version which only syncs to PPC!