Welcome to the forum. I'm going to disagree and say that writing the book is the easiest route. Even easier still is getting paid to do whatever it is you're good at, as a consultant or freelancer. It's not fastlane but you'll face many of the same problems as the other options, with no monetary investment to lose.
Definitely don't go hiring people for an app for your first venture. That's a surefire way to lose all your money and be left with nothing to show for it. If you don't know anything about software, don't have an audience to sell to, and have no idea of how to generate quality paid traffic, the probability of success is quite low.
Go read the gold and notable threads here. And, of course, read the books.