Troublemaker

Featured in the US Appstore! Here's what the reviews say:
"Perfect for on the move acid sessions, the Trouble Maker app faithfully recreates the sound of the original TB-303" - DJ Mag
"Troublemaker is absolutely no trouble at all to heartily recommend" - SoundOnSound
"If you want to make the bassline from Josh Wink’s ‘Higher State of Consciousness’ on the bus, this is the app for the job" - Factmag.com
"Top-notch stuff from a developer that just keeps getting better" - Musicappblog.com
"This app has been consuming all of my time this week! Love it!" - Discchord.com
Introducing Troublemaker: this is not a 303
The legendary TB-303 has magical properties; it is filled to the brim with analog shimmer. Its output jack is a gateway to a parallel universe and when you twiddle the filter knobs an army of highly trained pixies chisel the square waves from freshly harvested unicorn souls. So if you want a TB-303, you should buy a TB-303. But if you're after *that sound* Troublemaker will give you everything you need in spades.
Troublemaker sports a carefully crafted diode filter emulation and among the available oscillators are the typical raspy, nasal sawtooth and rubbery square wave with its oddball shape and shifting pulse width.
It also has the wow.
Troublemaker is fully Audio Unit (AUv3) compatible, so you can go wild running multiple instances in your favorite DAWs.
It also has:
- MIDI CC controllers for all knobs (predefined),
- Core Midi, Virtual Midi, Bluetooth Midi input,
- MIDI Clock Sync, MIDI Start / Stop support
- Realtime Mutation Probability Engine
- Standalone sequencer supports 1-64 steps
- Audiobus 3 support (audio + MIDI)
- Exports MID and WAV files from the standalone sequencer
- User manual and MIDI charts on ruismaker.com
- Comes with an extra AUv3 plugin version of a modded Troublemaker unit
And unlike the TB-303, it can actually sound like a bass guitar ;-)