ZMK is the recommended firmware as it's extremely customizable and was designed with wireless in mind. ZMK offers:
- Customizable keymap
- Use as a USB keyboard
- Use as a Bluetooth keyboard
- Switch between multiple Bluetooth centrals (phones, tablets, computers, etc) using user defined keys
- Low power consumption and long battery life
Those with questions about ZMK should join the Discord.
I recommend watching the firmware setup and customization video to get a sense of the process. It should be straightforward for most moderately technically competent individuals. A more thorough setup video and guide will be made available in May 2021 when ErgoDox Wireless begins shipping.
There are several other firmware options though I have no personal experience with them. The setup and configuration for these alternatives may require extensive programming and development knowledge.
Please note that QMK does not support nRF5, which is the family of microcontrollers that we use for our keyboards. While there are QMK forks with nRF5 support, we do not recommend them as they may be buggy and difficult for less experienced users to setup.