* Find an industry (ideally, an old fashioned one) where people are making money
* Find the single differentiator which will put your app apart in the already established industry (read or research what pain points are still not addressed by top 3 solutions)
* Make a web app, market it, refine it based on feedback, monetize the app
* Slowly incorporate all standard features expected out of a solution in that industry so you can shoot to be a market leader
I think this sounds great, but the key point is "read or research what pain points are still not addressed by top 3 solutions" which I think is very hard from outside the given industry.
Well there has got to be at least one "hard" part in making money, otherwise wouldn't everyone be doing the same? There is no easy way to make money or successful but it isn't impossible either.
I will give you my example. When I was starting out with Wingify (Visual Website Optimizer), I had absolutely no idea or industry connections in online marketing industry. But I started reading blogs, used existing solutions, talked to people and then eventually figured out that sufficiently large number of people do A/B testing, pay for it and right now it is hard enough to justify a new solution that simplifies it. The idea of "Visual A/B testing" wasn't something I realized overnight. It was a result of more than a year of trying to understand pain points of a "large enough" industry.
If you spend enough time researching an industry, you will eventually find some great opportunities.
Think of it this way: there are gas stations all over the place. But new ones open up all the time. Why? Do the owners know something everyone else doesn't?
I don't understand your point at all. What does opening a gas station on a busy street have to do with producing a useful tool for an industry about which you have no personal experience? Pretty much everybody understands what a gas station's customers need — they need gas.
How much gas per day? Where's the best place to open a station? Is it better to build one or look for one that's shut down and re-open? How often do you schedule tank refills? What regulations do you have to comply with?
And you'll go broke quite quickly if gas is all you can sell!
The point I was making (poorly, I admit) is that just about everyone who starts a business has to learn how the industry works one way or another. Nothing is ever as simple as it seems. "Producing a useful tool for an industry about which you have no personal experience" really isn't a larger obstacle than most entrepreneurs have to get past.