In a densely populated metropolis, drivers spend a lot of time and energy just to find a free parking space in a crowded parking lot. Watchmile is an indoor parking augmented reality navigation service that can guide drivers to find parking spaces in indoor parking lots where GPS signals are not available. The driver can check the congestion level through the mobile device before departure, and get the best route guidance to the free parking space through the head-up display (HUD). Oli, Watchmile's virtual assistant, connects the mobile device and the vehicle to provide each driver with relevant information in real time. Even in a congested parking lot, it can help drivers enjoy a relaxing and pleasant parking experience.