Google may be tracking the location of users even if they switch off the Location History option within their apps, a new investigation has found. The investigation found that devices running Googles Android OS and Google apps running on iOS devices were both sharing location data, despite users attempting to stop them.

The investigation was carried out the Associated Press and confirmed by computer science researchers at Princeton, and found that Google was able to track user locations even when Location Services were turned off.

According to Googles support page on the subject, “You can turn off Location History at any time. With Location History off, the places you go are no longer stored.” However, the research found that Google also tracks user locations through the Web and App Activity setting, which is turned on by default and doesnt make it obvious that it will track location data.

Even with Location History off, the research found that opening its Maps app would store a snapshot of where you are, while automatic daily weather updates on Android phones would also store a rough location of the user. Perhaps even more worrying, searches that had nothing to do with locations, using terms like “chocolate chip cookies” or “kids science kits”, would save precise latitude and longitude data, accurate to the square foot, to Google accounts.

“There are a number of differnet ways that Google may use location to improve peoples experience, including: Location History, Web and App Activity, and through device-level Location Services,” said a Google spokesperson in a statement made to the AP. “We provide clear descriptions of these tools, and robust controls so people can turn them on or off, and delete their histories at any time.”

The APs investigation was prompted by K. Shankari, a graduate reseracher at UC Berkeley who studies the commuting patterns of volunteers in order to help urban planners. She noticed that her Android phone prompted her to rate a shopping trip to Kohls, even though she had turned Location History off.

At the Google Marketing Live summit in July, the firm unveiled a new tool called local campaigns that aim to boost in-person store visits, with measurement data pulled from Google users location histories, while locaiton records stored in My Activity are also used to target ads.