It started with design principles. Personal, Relevant, and Connected. The goal was to help people get the information they needed to get them back to the people and activities that matter. The result is an experience that influenced the design language at Microsoft. This was a team effort and I acknowledge that
The lock screen was becoming overly complex. Volume controls, dialogs, security, and wallpaper were currently live. There were some concerns with the order of events on the technical side so I sat down with the developer and visualized the z-space order to make sure that the addition of the Live Wallpaper would work in the current framework.
After establishing the viability of the presentation layer I began sketching out interaction models for activating the feature. During this time I was also developing a feature with the photos team called Bragbook. Knowing that there were other features that needed similar functionality I designed the controls to accommodate for scale. In the interest of keeping these simple I forked the decision tree to Single Image vs. Dynamic/Multi Image. I believed that there would be some anxiety with this new feature when all the user wants is to change the photo. Providing the traditional alongside the dynamic feature we would measure the level of engagement and adjust accordingly once there was enough data.
I had early concerns with a user being able to easily identify their phone amongst other similar phones. Adding personal wallpaper to your lock screen was a way to easily identify your phone. Collaborating with the Project Manager we concluded that with the other ways to personalize your device in progress and scoped for the next release (Notification Tray, Calendar, and Custom Layouts) a user would be able to identify their device through these other features.