I’d do that in a heartbeat. I have a family to take care of. My customers can follow me to my next project.

> I’d do that in a heartbeat.

> My customers can follow me to my next project.

If you are willing to sell your customers to an ad firm, why should they trust your next project?

Because I have a family to feed, and I’m on their side offering them valid replacement for the app they’ve now lost to ad giants.

If you sold the app to the ad company, the terms of the sale are almost certainly going to prohibit you from building a competitor. You'd have to start a new venture in a different area.