Mobile app development agencies from a reputable source quoted me those numbers. I received two estimates at 7 figures and two at $250K. One quote was from my own employer. He’s a very senior engineer.
He’s one of those 10x productivity guys startups talk about.
All the agencies are U.S. based. I’d write the software myself, but I’m a Jr. QA tester. I’m not even close to good enough.