Although not exactly an iPad specific app, RapidWeaver 7 has just been released. It is a Mac app to help you build the website you want. It has just been updated to version 7. You do not have to know how to code in order to build a great website.
The app has built in templates from which you can build upon. There are a host of 3rd party themes and add ons that help you build your site. You can make your site mobile friendly, optimize SEO, and build blogs, portfolios or anything else for fun or business.
One of the newest features for RapidWeaver 7 is SEO Health Check that helps you fine tune your site. There are some responsive themes, refined UI and more reliable FTP for uploading your sites to host locations. You can see videos related to the new features here.
There are a series of tutorials you can review here.
There is even a large RapidWeaver community to ask questions and get help.
If you are interested in building your own websites with a mature app that can have you up and running in minutes, consider RapidWeaver 7.