Even though the app economy is less than five years old, it is expected to grow to $27 billion in sales this year. Apple (AAPL 0.37%) should continue dominating the landscape by grabbing two-thirds of all sales, or $18 billion. That's despite the fact that Google (GOOGL 1.50%) Android leads in unit market share by a significant margin. 

App monetization is strategically important as the driving force for the developers that provide complementary content. Google Play downloads have begun to grow, but Android users have shown less propensity to spend money. The gap between iOS and Android app revenue isn't shrinking anytime soon.

In the video below, Fool contributor Evan Niu, CFA, discusses how important app monetization is to the tech giants.