iPad integration is an optional add-on to your photobooth. Photobooth Supply Co. does not sell any iPad software directly. You'll need to purchase the iPad software separately from the developer directly (they can provide support for the integration).
An iPad integration doesn't take photos, but is a "watch folder" based program that allows for social media uploads on separate stations away from the booth on on top of photobooth software at the booth. It becomes a stand alone kiosk. In other words, it can help keep the lines moving by giving guests an opportunity to login and share their photos away from the booth on another kiosk.
You can always check in the PBSCO group for what people like at any given time. We do not specifically recommend any software, other than Queso, of course :)