Co-founder Michael Acton Smith, quoted in the same 2025 CNBC piece as Tew, says Calm deliberately ran lean and relied on organic word of mouth rather than paid marketing in its early years, reaching an estimated 8 million downloads before spending on ads. This is a third-party-published Q&A, so it is implied rather than stated, and the quote is Acton Smith's, not Tew's, though both are Calm co-founders.

Third-party marketing-agency analysis (not a founder statement) attributes a large share of Calm's organic reach to content and backlinks: a keyword-targeted blog with pieces like a "feelings wheel" post pulling tens of thousands of monthly organic visits, backed by a very large backlink base.

The same third-party analysis says Calm's team noticed most in-app usage clustered late evening (9 to 11 PM), read that as a sleep-search moment, and built YouTube content around high-intent search-and-sleep keywords rather than only optimizing Google search.

CNBC's own reporting, not a founder quote, describes Calm bringing on celebrity narrators and investors for its Sleep Stories feature starting in 2018, beginning with Matthew McConaughey, followed by LeBron James publicly praising the app and Harry Styles both narrating a Sleep Story and investing. This is press narration, not Tew's or Acton Smith's own words, so it is marked implied.