Other orchestral instruments, on the other hand, are typically made for a specific key but can transpose into other keys with some effort. But, if you have 3D printed your instrument like this ...

but sometimes you just need the old nought-through-nine, and in a big, visible package, to boot. For those circumstances, consider whipping up a set of these 3D-printed seven-segment displays.

While AdmiralSym’s case was designed for one specific phone, the instructions and design files you’d need to 3D print your own case are available at Printables, so folks with the know-how ...

While many DIY handhelds are powered by a Raspberry Pi or some other single-board computer, the HaPlay Go Zero is basically what you get when you stuff an old smartphone into a 3D printed case ...