Apple has acquired WifiSLAM, a Wi-Fi-based indoor navigation company, indicating that it may be planning to add indoor navigation to its mapping service. The news was reported by The Wall Street Journal and confirmed by an Apple spokesperson.

WifiSLAM’s software lets people pinpoint their location within a building using ambient Wi-Fi signals from routers that are already present inside, providing accuracy of around eight feet. Apple reportedly paid $20 million for the two-year-old company, a relatively small acquisition, but a definite asset in the competition against Google’s dominant Maps service, which offers its own crowdsourced indoor mapping functionality.