Geo-targeting refers to delivering ads to people meeting a specific targeting criteria and who enter inside of a defined radius using the same geo-fencing location technology. The key difference is geo-targeting hones in on specific consumer targeting criteria like demographics, behaviors, interests, as well as where the person is located. For example, targeting and delivering a Starbuck’s mobile ad on a person's phone when he or she is in or near a Starbuck’s retail store after he or she has passed a Starbuck's ad on an OOH or outdoor billboard. You often need bigger geos to do this since you are not showing the ads to EVERYONE inside the geo-fence, they must also meet the targeting criteria. If you are only interested in hitting only a specific consumer demographic that can be very narrow in focus, then you should be doing geo-targeting.
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