11/10/20: ROLI has released Equator 2. Equator is one of my (Roger's) favorite MPE-compatible synths and now includes an expanded sample library, granular synthesis, and lots of improvements all around.
11/10/20: The GeoShred 5 iPad app from MoForte now includes 6 of Audio Modeling's SWAM physically-modeled acoustic instruments as in-app purchases for only $15 each or $75 for all 6. That's an incredible value for the best violin, cello, tenor sax, flute, clarinet and oboe sounds on the market for expression play from LinnStrument.
One of my favorite synths is Surge. It's highly versatile and full-featured, MPE compatible and very expressive, runs on Mac, Windows and Linux, is open source, and it's FREE. Learn more and download it here.