Examples describe systems and methods for performing a multi-step approach for map generation and device localizing using data collected by the device and observations of interdependencies between the data. An example method includes receiving logs of data collected by the device, determining a constraint for locations of the device according to a comparison of data in the logs of data with available known signal strength maps of corresponding data, and performing a first simultaneous localization and mapping (SLAM) optimization of location estimates of the device using the logs of data and the constraint as a first initialization. A second SLAM optimization is performed using outputs of the first SLAM optimization and relative estimates of the device based on dead reckoning as a second initialization. An output location estimate of the device is provided based on the second SLAM optimization.