Contextual advertising doesn't imply the system's completely ignorant of the device's detected language or geolocation. It simply means you're not employing a s

Contextual advertising doesn't imply the system's completely ignorant of the device's detected language or geolocation. It simply means you're not employing a series of correlated requests across a stable identifier (browser cookie, IDFA, etc.) to model some outcome, e.g. probability to purchase, for a given advertisement. Instead you infer a set of user features based on the domain/content _and_ attributes of the single request: device, geo, time of day, language, etc.