I am trying to find a group of iOS music apps that caught my attention sometime ago, which I’m failing to track down (thank Apple for removing the wish list feature, who would ever want that?). There were 3 or 4 small apps made by the same developper, all very minimalistic and elegant in design, mostly made up of monochrome, pastel-coloured boxes. They drew some inspiration from the OP-1. I think I remember one of them being a delay / filter, and another one being some kind of karplus-strong synthesizer. Does anyone recognize this?