Xilisoft iPad to Mac Transfer lets you backup your iPad. This app will display all the contents of your iPad whenever it is connected to your Mac. It will show all the music, movies, photos, ringtones and books. You can easily transfer any of that back to your Mac, without using iTunes. Additionally, you could use this app to transfer content from your Mac to the iPad, which would let you skip syncing with iTunes as well.
The main window shows a brief summary of your iPad, along with a snapshot of the device, its capacity and a graphic representation of how much space is used in audio, video, photos, books, and others, and how much space is available. On the left part of the screen, you will see all the data categories (music, movies, etc). Clicking on each of those will bring up a list of all the content you have on your device, if there is any. So, if you want to back up a song, simply click on Music, check the song or songs that you want to download, and click on the "Copy" button at the bottom of the screen.
All in all, this app works, but I noticed that the "Purchased" list didn't show any of my purchased items, "Books" didn't show my iBooks, and I couldn't put a movie on my iPad using this app. The rest of the features worked well.