Hi all! Here is a breakout board I put together in the shape of a thumb keyboard for the Teensy 3.2.

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  • Beginner friendly through hole soldering.
  • 60 keys arranged in a familiar qwerty layout with number keys arranged in a numpad.
  • SPI, I2C, and 2 additional GPIOs broken out. Aside from these pins all others are used to read the key matrix.
  • Teensy can be rotated with the micro USB facing up or down. Breakout pins will only work as expected with USB facing up.

Lots of photos available at: https://hackaday.io/project/162281-t...thumb-keyboard
3D Model of a Raspberry Pi Handheld Proof of concept Project: https://www.thingiverse.com/thing:3209958
KiCad and STLs: https://github.com/AnthonyDiGirolamo...thumb-keyboard

I'm still waiting on a rev v1.1 board and will update when that arrives. Code is working but it needs some cleanup before I can share.