While some keyboards like this might use a standard USB connection to join the two halves, the ZSA Voyager uses I2C instead and even breaks the I2C bus out with a pogo pin-compatible connector.

grab an FTDI chip and a USB connector, and simply build my own USB to serial adapter that uses pogo pins instead of pin headers. This actually wouldn’t be that much work — two hours to design ...

However, upon closer inspection, you’ll see that the phone has a pogo pin connector at the back and clearly visible screws that are just begging to be opened. These two elements form the whole ...

Expansion port on the back lets you add Outfits with added functions Review HMD's Fusion smartphone has a pogo-pin port on ...

The Mecha Comet is made for hackers and makers, running Debian with a custom touch UI and lots of upgradeability.