This was largely programmed on a venerable Motorola Droid 4 running maemo-leste, which is pictured below alongside the larger PinePhone by Pine64. I was greatly suprised by how up-to-date this descendent of Nokia's Maemo OS turned out to be. In combination with the small form factor of the Droid it delivers a fantastic on-the-go development platform (note: the escape key does not register in PICO-8, but that is not really a problem if you use an external editor like Geany).