after You finished Your database using the trial version, You can copy (or mail, or via dropbox) that db to the iPad and use it there - no problem. You just can't open that db on Your desktop after the trial period - then, You need a licence of FileMaker Pro (or FileMaker Pro Advanced)
Ethically? not touching that.
My advice to anyone that is going to develop a filemaker solution, is to (purchase and renew) always have a current copy of FileMaker Pro Advanced for development purposes.
Note that filemaker is cross platform, so you can purchase a license to use on windows now, and then reinstall using that same license when you switch to mac later.
Thank you for the quick reply guys.
I have no intention of not paying for the software, I just want to get started now as I have a project I want to get started on.