A large variety of systems and applications are offering localization and navigation services for outdoor environment. However, people typically spend most of their time in indoor environments. Hence, it appears the need for updated indoor maps especially for public spaces. The majority of current research endeavours focus on the indoor positioning problem. Obtaining spatial information in indoor environments is a challenge. Inertial sensors, accelerometers and gyroscopes, which are available on most smartphones, are used for positioning. The barometers built into smartphones are used to estimate the vertical position or to recognize vertical movements. The magnetometers built into smartphones are used for attitude estimation as part of a positioning system. Indoor positioning using WiFi signals is heavily investigated. The common approach to position estimation in these works is based on the received signal strength (RSS) and the fingerprinting method.