How does Umano make its money? Do they charge for the app or play ads? Sell data? I've always felt it questionable ethical territory to take somebody else's wo

How does Umano make its money? Do they charge for the app or play ads? Sell data? I've always felt it questionable ethical territory to take somebody else's work, slap ads on it, and pocket the money. "Aggregators" have been doing that forever, though.