Niantic's Harry Potter mobile game has yet to cast a spell

Take the location-based engine and augmented reality smarts that produced Pokémon Go, mix in the popularity of Harry Potter and you have a guaranteed hit, right? That's the logic behind Niantic's recently released Harry Potter: Wizards Unite, but early results suggests the new game may have a tough time living up to expectations.

By the numbers: It's down to No. 73 on App Annie's chart of top-grossing iOS apps, far below Pokémon Go at No. 15 and also below a different Harry Potter title from Jam City.

• Apple's own chart has it at No. 52, ahead of the other Harry Potter game, but well below Pokémon Go at No. 7.
• The app has more than 5 million downloads on the Google Play store, but isn't featured at all in its chart of top-grossing games.

Why it matters: Niantic's goal is to have a platform powering a range of homegrown and third-party-developed titles using its engine. To reach its long-term goals it would ideally like to show it can generate and sustain multiple fan bases simultaneously. It did that to a degree by maintaining its first game, Ingress, even while Pokémon Go took off.

Yes, but: Almost anything will look lackluster compared to Pokémon Go, which was an overnight smash. Even if Wizards Unite isn't an immediate viral hit, it can still be a lucrative game, but it will have to show steady growth over time.

• And, as long as Niantic can keep people using its platform (in any incarnation), it will build on its market-leading — and proprietary — real-world AR platform.

What they're saying: Venture capitalist Megan Quinn, whose firm Spark Capital is an investor in Niantic, says the Harry Potter game needn't match Pokemon's early success.

• "Pokémon Go wasn’t our measuring stick for the game. ... We’re enthusiastic about the AR-real world platform that Niantic is building."

The big picture: Niantic says it has a multiyear storyline for Wizards Unite and a number of marketing efforts, including promotional tie-ins with AT&T and mall giant Simon plus a live event in Indianapolis over Labor Day.

Go deeper: Pokémon Go ups its augmented reality game