Humans dreamed of flying like a bird for centuries before hot air balloons finally took people into the skies. At first the designers of Birdly took the dream a bit too literally and used a physics engine to model airflow around virtual wings. But it turns out to be hard for humans to fly like an actual bird, learning to flap their wings at the right angle and catch thermals to spiral up. To simulate the effortlessness of dream flight, Rheiner made the interface more metaphorical and intuitive. By twisting your arm you control the pitch of the wing: Tip up to soar higher, and tip down to dive. Catch the air with one hand to bank. To climb faster, you can vigorously pump both wings. Pistons provide realistic resistance, and a fan is calibrated to make the windspeed match your virtual velocity.
It’s admittedly a bit awkward to climb onto Birdly. You bend over a padded frame, strap on a tight headset and headphones, then hook your hands into wooden wings. But then the screen flips on and you find yourself floating above the city, watching your bird-shadow drifting across the rooftops. If you crane your neck, you can see your brown feathers ruffling in the breeze. After a few seconds, flying feels natural.