Roxsyn is the “world’s first metamorphic guitar synthesizer” for iPad. The app lets you plug in your guitar and, when you play it, synthesizer sounds come out. It also offers a full suite of knobs to tweak and shape the resulting sounds, just like a regular, keyboard-driven synth.

But — and this is important — it’s not just using your guitar as a MIDI controller for a normal synthesizer. Let’s take a look.

Teenage Engineering’s awesome, pocket-size OP-Z synth can now record and use samples. Thanks to a massive software update, it can now sample live audio in through its mic, or via its USB-C port. And yes, if you hook it up to an iPhone or iPad via USB, it shows up as a standard audio interface: You can record from, and send audio to, the OP-Z in lossless digital quality.

Today we’re going to check out these new features. A few limitations prove annoying, but Apple users should feel accustomed to that by now.

Here’s some pretty big news for iOS musicians: AudioKit’s Digital D1 synth is now an Audio Unit. What? That means that, instead of running as a standalone app, you can now run it as a plugin inside your music app of choice. It also means you can run more than one copy, putting one instance on each track of GarageBand, for instance.

And what makes D1 more interesting than other synths for iOS? A few things. One, it’s open source and built by volunteers. Another is that it looks and sounds amazing. And finally, it’s totally ’80s, giving you the synth sounds of pop music’s best decade. Radical.

Did you ever wonder how a synthesizer works? It’s all just “electronic noise,” right? Well, yes, it totally is. But if you’d like to know a bit more than that, Berlin-based Ableton will teach you. The electronic music giant launched a website that puts a synthesizer inside your browser, and uses it to teach you exactly how a synth works.

The synth simulator works great in Mobile Safari, too, but if you use Google’s Chrome, you can hook up an actual keyboard to your Mac and use it to play. That’s thanks to Chrome’s support for Web MIDI, which Safari doesn’t offer.

Let’s have a quick look at this cool teaching tool.

Factory is an aptly-named new iPad synthesizer from SugarBytes. In fact, calling it a synth is underselling it — kind of like calling GarageBand a “tape recorder”. Factory does synthesize sounds, but it also has built-in effects, a sequencer, an arpeggiator, and a totally wild DJ-style crossfader, which lets you morph between presets.

The app is ultra-flexible, as capable of finely-crafted sound design as it is of sonic mayhem.

The Synclavier is a digital synthesizer from the early 1980s. Synclavier Go! is an iPad app that mimics the classic synth. But this post isn’t about those. It’s about the Synclavier Knob, an accessory for the app.

The Synclavier Knob is a single knob on a mounting plate the size of an iPad mini. That’s it. Oh, and it costs $399.