Native Instruments and Ableton have had incredible success with their custom MIDI controllers that integrate with their DAWs (digital audio workstations), Maschine and Live, respectively. Native Instruments' Maschine (yes, it's the name of the hardware and the software) and Ableton's Push are pretty much the gold standard for integration between music-making software and hardware. Serato is hoping it can capture even a sliver of that magic with its pairing of Slab and Serato Studio.
Arturia's KeyStep is one of the most popular MIDI controllers ever made, especially with modular synth users and the DAWless crowd. It's small, cheap, has an easy-to-use sequencer, and offers decent connectivity.
The core of what makes the KeyStep beloved remains unchanged: 32 solid minikeys with aftertouch, a small footprint, decent connectivity options, and low price. The mk2 features USB-C for power and MIDI, five-pin MIDI in and out ports, analog sync in and out, a sustain / expression pedal input, plus CV and gate outputs for hooking up modular gear. The headlining updates here are the new generative capabilities, Mutate and Spice, borrowed from the company's Freak line of synths.