Does anyone have a good list of small, handheld, battery powered mini synths, grooveboxes, effects and other noise-makers?
I've preordered a Dirtywave M8 which seems like an awesome piece of gear and it's got me really excited at the prospect of using interesting dedicated hardware machines that I can take to the park or mess with on the sofa.
The obvious ones I've come across so far are:
Korg Volca range
Roland mini synths and aira compact ranges
Teenage Engineering OP and POs
But these all seem a little uninteresting to me and just rehashed tiny versions of older gear and/or aimed at lo-fi producers.
Some less obvious ones that have my attention are:
Monome Norns
1010music lemondrop, fireball & razzmatazz (not battery powered but easily powered by a USB powerbank)
Bastl microgranny and kastl
Korg NTS-1
Korg Monotrons
Audiothingies Micromonsta 2 (again not battery powered but can be via powerbank)
The Modal CraftSynth 2 is in this category. I have one and I'd say I like it (but maybe not love it) - great for a class of digital wavetable sound no analog synth can match (but also does decent analog-ish subtractive synthesis). The SH101-style sequencer in the CraftSynth2 is a bit different to the usual, but in a fun way - works quite well for acid IMO.
The Korg NTS-1 is handy as long you are sequencing / playing it via an external controller - the ribbon keyboard on it isn't useful. It's versatile since it also makes a good effects unit (which is how I use it almost exclusively). There are a bunch of free and paid 'plugins' you can load onto it to expand the sound palette too, and even write your own using the open SDK if you are so inclined.
Deeper into DIY, Shruthi, Anushri, TSynth and (sadly unobtainium) Plinky probably fit on this list.