What new AI-driven ad channels and media-buying agents should founders watch beyond Meta and Google?

AppLovin's Axon engine opened self-serve to all ecommerce advertisers in mid-2026 and already rivals Meta's Audience Network on conversion for some categories, TikTok's Smart+ keeps widening automation, and agent-to-agent media buying (with standards like AdCP) is moving from concept to early production. For a founder the play is to master one core channel first, then use these emerging channels as cheap arbitrage while big advertisers are still slow. Expect your role to shift from clicking buttons to setting goals and guardrails for buying agents.

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