Hello there,

just like Mike, I'm going to add my shameless plug here, as I work for the company that makes iTablo.

Although it's not exactly an alternative to Adobe DPS, you might want to check it out anyway. The product at its core is a PDF reader, meaning that you start from a PDF file coming from any source and add all of the interactive content in our own designer that can be download for free from our site here: https://www.itablo.com/download/. All you've got to do is signup for a free trial license.

When you're done, you deploy your work on your iPad through iTunes and our iTablo PDF+ Viewer, which is a free app available on the App Store.

We offer two kind of solutions for publishing on the App Store: iTablo Book that has a fixed one-time price and your app will contain just one PDF, and iTablo Kiosk which is an online kiosk where you can publish all you want and that offers features like subscriptions, push notifications, analytics, etc.. for an annual subscription price.

You can check some videos of the designer and viewer here: https://www.itablo.it/video/

I'm afraid the subtitles aren't in English. There will be new videos and a new international site online soon, but in the meanwhile you should be able to see an overview of the products.

Best regards.