Defonic - Create a unique sound environment at home or in the office
AudioKit Synth One - Free & Open-source iPhone/iPad Synth 🎹
Noisli - Noisli is a fantastic background noise and color generator for working and relaxing. Online soothing ambient sounds like White noise, Rain and Coffee Shop.
Sampulator - Make (and record) beats on your keyboard
Noizio - Feeling that the noise of the big city is too much for you to bear?
Logic Pro X - Music production.