1. A method of determining whether to add a landmark to a map for navigation, the method comprising: autonomously navigating a mobile device using the map, and while navigating the mobile device, performing the following: retrieving an image from a visual sensor; comparing features from the image to a plurality of stored features; generating a list of matching landmarks from the comparison; filtering matching landmarks from the list based on reliability tests; proceeding to a landmark creation process when there are no remaining matching landmarks in the list; and providing match results to a simultaneous localization and mapping process for navigation of the mobile device when at least one matching landmark remains in the list; wherein navigating, retrieving, comparing, generating, filtering, and proceeding are performed under the control of electronic hardware.