Yes, you can use your smartphone as a key with Kevo Smart Locks. Kevo has a mobile application that allows users to unlock their doors using their smartphones instead of traditional keys. This feature utilizes Bluetooth technology to communicate with the smart lock, enabling users to gain access simply by being in proximity to the lock. Once the application is installed and the lock is set up, users can easily manage access for guests as well. The app also allows for additional features such as tracking who enters and exits the property, setting up temporary access codes, and receiving notifications when someone unlocks the door. To take full advantage of these features, it is essential to ensure that your smartphone is compatible with the Kevo app. More specific information about device compatibility can typically be found on the official Kevo website.