We are building an indoor navigation SDK that will allow developers to catch events like "user walked into the TV section at a Best Buy" or "user walked into a workplace cafeteria". To deliver this, we need to build maps of large numbers of indoor spaces around the world, and then later identify a user's position within such a map using only those sensors that are available while their phone is in a bag or pocket. To solve the mapping problem, we're building "taskrabbit for mapping" -- a system where people are paid to map out floorplans and wifi networks in indoor spaces. To solve the the localization problem, we're building an Android SDK that combines wifi and inertial sensors to estimate positions