Birdie was started in 2022 by two childhood friends from Hellebæk, just north of Copenhagen. Hans Høite Augustenborg had been thinking about how much of our lives we spend indoors in air that is quietly degrading our focus and our sleep. The reference point was the original sentinel of bad air — the canary in the coalmine — and the design followed from there: a small physical bird that tilts down when CO2 rises and rights itself as the room ventilates. The first run launched on Kickstarter in April 2022 and raised almost half a million dollars in thirty days from backers in more than sixty countries. Birdie 2.0 is the current generation: recycled-plastic shell, Swiss-made CO2 sensor, USB-C power, no app, no screen.