That's why it's important to capitalize on your own interests and expertise. You already intuitively know what products or services that might be useful to others that would benefit from your innovation.
Yes, be inspired by success stories of others, and talk to others about the process of finding and capitalizing on a niche. Carefully crunch numbers and test the market, but YOU find your own niche for yourself.
If you are only in it for the money, become an investment banker or a funeral undertaker! Your success would be all but guaranteed but money can't buy happiness. Do what you love and the money will follow. Best of luck.
Use Adwords to find a keyword or phrase with 1000- 30,000 searces a month and less than 2 million results when you search for it on Google. And it must be a keyword where you can sell them something.
ie. People searching for 'How to get free Internet' probably arn't going to be looking to spend money on something.
This depend on you that which way you use to find it and in which niche you have most interest.
http://technosoftwares.com/mobile-applic...
One that is steadaly going up in value.
Look long and hard