The idea and name behind this project sounds awesome. But I don't understand how it is still airgapped if the transactions are still generated by online devices, or is there something I'm missing?
The transaction is generated on the every-day device with the AirGap Wallet installed, this device has internet connectivity. The signing happens on the air-gapped device with the AirGap Vault app. Broadcasting to the blockchain then will be done again with the AirGap Wallet app.
If you're referring to the approach with AirGap Vault & AirGap Wallet on the same device, then it's not air-gapped anymore but provides still additional security to a one-app approach.