Definition: Cross-device targeting is a marketing strategy that identifies individual users across multiple devices — smartphones, tablets, desktops, smart TVs, and wearables — and serves them consistent, coordinated advertising messages regardless of which device they are using at a given moment. The goal is to create a unified view of the customer journey across all touchpoints.
Why It Matters: Most consumers now move fluidly between devices throughout the day — researching on mobile, converting on desktop, streaming on connected TV. Without cross-device visibility, advertisers risk duplicating impressions, missing attribution for conversions that span devices, and delivering inconsistent creative experiences. Cross-device targeting is foundational to frequency capping, sequential messaging campaigns, and accurate multi-touch attribution.
How It Works: Cross-device identification uses two primary methods. Deterministic matching links devices to a single identity using a known identifier — typically a logged-in user ID, email address, or hashed customer record. This is highly accurate but limited to authenticated users. Probabilistic matching infers device relationships using statistical signals such as shared IP address, location patterns, browser fingerprints, and behavioural similarity. Identity resolution platforms (LiveRamp, Neustar, The Trade Desk’s UID2) combine both approaches to build device graphs used by advertisers for targeting and measurement.
Related: Identity Resolution, People-Based Marketing, Frequency Capping, Multi-Touch Attribution, Connected TV Advertising