In our release at the end of this month (Fed 2013) we will be adding support for uploading photos and videos from an iPad/iPhone (iOS).
iOS only supports those formats within the web browser, PDF isn't supported for upload on iPad because iOS restricts it.
In our 2/21/2013 release, we added the ability for respondents to upload attachments as part of their web form submissions on iOS (iPad/iPhone) and Android devices.
iOS only supports image and video uploads (the OS doesn't allow any other file types to be uploaded).
Android supports any type of file including audio, video and images.
Give it a try and tell us what you think.