The Digitech iPB-10 has taken the familiar RP series pedalboards and replaced the interface with an iPad. The iPB-10 can be used with the original iPad, iPad 2, or new iPad (3rd generation iPad). There is a plastic tray which the iPad sits in, which can be changed for your model of iPad. If the thought of your iPad being on the floor bothers you, you don't need to dock the iPad but could use an extension cable (Dock Connector Extender Extension Cable, not USB cable) and mount your iPad to a mike stand or a music stand.
The iPB-10's sound is still produced by the pedal itself (and it will function without an iPad), but now you can edit patches and manage your tone library through a nice graphical iPad interface. For those without an iPad, this pedal is either of no value or a great excuse to buy an iPad. The iPad connects to the iPB-10 via the 30-pin Apple dock connector. Once connected, you launch the free iPB Nexus app to interact with the pedalboard. You can also launch other iPad apps while docked, such as GarageBand, a metronome, the iPod music player, or a cool music trainer like Anytune, or tablature apps like Guitar Pro. In GarageBand, the iPB-10 sound is recorded in the Voice Recorder. Sound output from the iPad is routed out through the pedal's outputs. In the Nexus iPad app settings, you can adjust the mix between the iPB-10's and iPad's sound for both the 1/4" outs and the XLR outs.
When not docked in the iPB-10 pedalboard, you can still use the iPB Nexus app to edit patches or work with the tone library. Some people have gotten the idea that the app is usable for sounds without the pedal through another guitar interface like iRig, but again, the pedal hardware does all the sound processing and the iPad is just a "pretty face". If you are wondering if you'll like the iPad interface, just download it to your iPad for free and play around with it. I have seen reviews that complain that the app is buggy and has crashed, but I have yet to experience any real problems and my experience is that DigiTech support guys can help you through any issue.
The iPB-Nexus app also has a built in patch library, with tabs for factory tones, your patches, and the patches currently assigned to the 20 patch banks. You can store all the patches you want, make long meaningful names, and tag the patch with song name, artist name, genre, and a large "description" field to write detailed notes about the patch if you wish. You can backup your library or individual patches from the iPad either by email or iTunes. A simple click of a patch file from a friend from email on the iPad or a website such as the user community at http://ipb.mediamanhost.com/, and the new patch is added to your library in the app.

The iPB has 20 banks of 5 patches that are assigned to the 1 through 5 foot switches at the bottom of the pedalboard. To switch between banks, you either swipe your finger across the bank numbers at the bottom of the iPad screen, or stomp the UP and DOWN foot switches on the iPB-10. After switching banks, you then press on the iPad or stomp the foot switch of the patch 1 through 5 in that bank.
Each patch can have 5 effects linked to the A, B, C, D, and E foot switches. While many Digitech pedals will let you assign more than one effect to a foot switch, the iPB only allows one effect to be linked to a switch. If you want to switch multiple effects at once, you are better off using a separate patch in the same bank. When you assign an effect to the switch, it shows up on the main screen in the order assigned to the switches, regardless of the order of the effects in the signal chain. And for us older more mature players, I hope you recognize the pedal by color, because most of the pedals have small print that is hard to read at a distance.

The iPB-10 has a built-in tuner. You can press a button in the top right corner of the display to activate the tuner, or press and hold any of the 1-5 patch foot switches to engage the tuner. As you hold the switch down, it will first say "BYPASS" and then eventually switch on the tuner. When you are done tuning, just tap a switch to return to playing.

Click here to see a closer view of the back of the unit. The "looper control" line out is not yet supported, but Digitech is working on it... so any looping would have to come from an iPad app and won't be controlled with your feet. The pedal does support both an external stomp loop and output to amp effects, along with stereo 1/4" and XLR outs, and a 3.5mm headphone jack.