Atteste is Strava for Art — a mobile-first collection app with a built-in AI companion (Atelier), a genuine free tier, and provenance recorded at creation. Photograph any work and Atelier names the artist, medium and period, then seals it with a tamper-evident, Bitcoin-anchorable certificate. First Witness lets artists record a work's story at the moment of creation. iOS, Android & web. Free tier, no card; paid from $9.99/mo.