In AdWords, advertisers can track store visits from the Display Network campaigns, on ads served on the Google Display Network (GDN). This allows advertisers to optimize their campaigns, keywords, devices, audiences and contextual (topics) targeting that drive more visits to the local businesses. In-Store visit conversions also bring insights on the return on investment (ROI) on creative, spend and bids.
To setup a campaign with store visits as a goal, advertisers need to have a Google My Business account linked to the AdWords account, with store locations already created and validated. After this, advertisers need to contact the AdWords dedicated account manager to know if the advertiser and country is eligible.
After being whitelisted by the Google account manager, advertisers need to ensure location extensions are active in the account. According to Google, advertisers also need to have thousands of ad clicks and viewable impressions and Google need to have sufficient store visits data on the backend to attribute to ad click or viewable impressions traffic and pass the user privacy thresholds.
Here a video how it works:
Hotels, auto dealerships, restaurants, and retail stores are the most common advertisers trying to bring users to the physical locations with online ads.
In programmatic (working with DSPs instead of Adwords), there footfall providers like Factual and Adsquare that can measure all ad impressions in-app, and not only on the Google Display Network (GDN).