The hardware (US$39.99) is pretty simple. It gives you a quarter-inch line-in for your instrument, an eighth-inch output to go to headphones, mixer, speakers, etc., and it has an eighth-inch male jack to plug into your iPhone (no iPad app available yet, but the hardware works if you don't mind pixel-doubling the app). Unlike the iRig, it requires two AA batteries, but after daily use for two weeks, I haven't killed the batteries that came with the unit. The extra power gives you added volume on the output, as well as more advanced noise-canceling options.
The software on the iPhone is where the party really starts. The free AmpKit app starts, of course, with a metronome and tuner, which are both well done, and it includes a dual-channel amp, two mics, and two pedals. AmpKit+ is available for $19.99, and includes four amps, two mics and, eight pedals. It looks like buying the AmpKit+ bundle saves you 50 percent off of buying the gear individually. Compared to buying the actual hardware to achieve these sounds, of course, it's a tidy savings. All of the additional gear can be purchased from within the app. Most pedals are around $3 and range up to $6.99.
Whereas the AmpliTube software limited you to three pedals and custom amp settings, you can have as many of the available pedals as you want in an AmpKit setup. Depending on the pedals you have in your arsenal, AmpKit will offer you preset combinations of amps and effects. These range from Snappy Acoustic to Nu Metal Valve King, with plenty of blues, funk and decades of rock history between. They make a great starting point for finding a sound, and the effects are easy to tweak individually. You can duplicate existing presets and save your edits, or you can build a new set from scratch. I had all of the additional gear available to me for the review, and I was hard pressed to find a sound I couldn't match with AmpLink.
Within a setup, tapping the amp gives you all of the controls you'd find on a real head, and tapping the cabinet gives you control over the mic you're using. Tap the dials on any pedal, and you get all of the options for that pedal. It's all very intuitive, and settings are exactly where you'd expect them to be.
In addition to the metronome and tuner, the base application also allows in-app recording. You can add backup tracks, or you can record your dry input to try with different setups.
At this point, you're probably wondering how it sounds, right? It sounds awesome! Some of the effects obviously won't be everybody's cup of tea, but a little tweaking and a decent set of speakers or headphones, and you can pull off some amazing sounds. I've plugged both bass and guitar into it, and I've played with sounds ranging from direct box to highly experimental (the Octopuss pedal has some insane settings). The results are high quality and gig/studio-worthy, especially in combination with the noise filtering capabilities. In short, I've been having a blast.
I'm told that decisions are still being made on the future of an iPad version of the software, but I'd like to cast my vote in favor of it. The iPad version of AmpliTube is great and a major selling point for the iRig. I hope that we'll see a similar, iPad-optimized version of AmpLink soon. Either way, if you're looking for an iPhone-based means of building up your axe arsenal, AmpKit and the AmpKit LiNK make an excellent option. The AmpKit LiNK hardware retails for $39.99 from Peavey, and more info on the iPhone app is available from Agile Partners.
Also, guitarists and bassists, be sure to check out GuitarToolkit and TabToolkit from Agile Partners, if you haven't already. They're handy.