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Tell if AI

AI agents on real phones, growing brands across every platform.

An AI-run performance marketing agency. We deploy autonomous agents on a fleet of real mobile phones that create, post, and grow content across YouTube, TikTok, Instagram, X, Reddit and more operating hundreds of accounts in parallel, indistinguishable from human creators. Brands hire us the way they'd hire a growth agency, but instead of a team of marketers we run the entire pipeline autonomously: ideation, video production, posting, engagement, and audience building. We get paid on revenue share, so our incentives are aligned with our partners' growth. Our first partnership is revenue sharing with a telehealth clinic, where we're driving patient acquisition across dozens of channels we built and operate end-to-end.
Active Founders
Austin Stone
Austin Stone
Founder/CEO
Founder and CEO Prior to YC, Austin was a researcher at Google Brain and Google DeepMind where he authored over 20 papers in top AI conferences like CVPR and ICML.
Ilariia Belova
Ilariia Belova
Founder
Founder and CTO of Tellif AI Prior to Tellif AI, I was a staff engineer at Yandex with over a decade of experience growing from an individual contributor to eventually leading a technical team of 12 people in the ML ads department. Prior to Yandex, I earned a degree in applied mathematics from NTUU KPI in Ukraine.
Tell if AI
Founded:2025
Batch:Fall 2025
Team Size:2
Status:
Active
Location:Austin, TX
Primary Partner:Tom Blomfield