- Uconsole bigger one https://www.clockworkpi.com/uconsole
- devterm https://www.clockworkpi.com/home-devterm
- Beepberry - https://beepy.sqfmi.com/
- https://liliputing.com/beepberry-is-a-79-hackable-pocket-computer-kit-with-a-blackberry-keyboard/
- Colorberry - https://www.elecrow.com/colorberry.html https://github.com/hyphenlee/colorberry
- PC Pilet old but cool looking one - https://soulscircuit.com/pilet
- https://www.raspberrypi.com/news/pilet-mini-pi-5-modular-computer/
- ESP32 - ESP32 is a SoC, example of handheld using it is the LILYGO T-Deck Plus - https://lilygo.cc/products/t-deck-plus-1
- https://linuxgizmos.com/updated-t-deck-plus-an-esp32-handheld-device-with-gps-and-lora-support/
- Mecha Comet with the switchable keyboards - https://mecha.so/comet https://www.geeky-gadgets.com/modular-linux-handheld-mecha-comet/
I also like ANBERNIC RG28XX and PinePhone/PinePhone Pro with or without the keyboard/battery extension.