I recently designed a poster for a friend's charity boxing event. I'm doing one version for print, but thought it would be cool to add a 'BUY TICKETS' button linked to the ticket URL. The poster was created in Ilustrator, finished in Photoshop then placed in Indesign where I created the button, and added the link. I then exported the file as an Interactive PDF. It was originally an A4 size, but at nearly 10MB I downsized to iphone size, anyways, when the PDF displayed after creating the button wasn't visible. I decided to email it to myself to test it...when I opened it from the email, the button was visible but scrolling over it didn't do anything, and when I downloaded it to the desktop the button was invisible again. i would ultimately like for people to be able to email the poster to each other then hit the button to go to the ticket URL.....
You don't mention how this PDF is being viewed. Interactive PDF viewed through any app besides Acrobat or Reader on a desktop is a crapshoot. This is especially true on mobile devices.
BTW, I would have simply opened the PDF in Acrobat and added the button there.
That was going to be my next question. Adding an interactive item to a PDF narrows down the practicality of it in that it can only be properly viewed with certain applications right?
Which I doubt the majority of people who are viewing this will have. Which makes it a bad idea?
Secondly, you mention adding the button in Acrobat. Is this a more efficient way than adding in Indesign?