At Sonder, we launched a feature allowing guests to download a mobile key and enter their units securely, using near-field communication (NFC) technology.

This feature was put on the roadmap at the beginning of the pandemic as an effort to make our spaces as safe as possible. As such, the timeline was tight, and we were under pressure to get this feature out as fast (though safely) as possible.

The problem of massaging external vendor APIs, downloading and storing, and broadcasting a mobile key was an extensive end-to-end engineering lift. The app had to communicate with our backend, which in turn had to authenticate with the external service providing the mobile keys for their locks, and then store the digital key within the app.

Security is extremely important for short-term rental locations, so extensive UAT and testing was done, as well as a gradual rollout, to ensure the feature was stable and secure. The feature was surprisingly stable during UAT, only requiring a few tweaks and fixes before rollout began. A testament to the team's engineering chops! 💪