To tell you the truth, top Android apps are free to download but their developers don’t get to keep a dime. The fact is that most of these are developed by freelancers or employees of software companies that produce mobile software applications for a living. Because these developers have too much to invest in themselves, they can’t provide support for paid apps and they won’t pay for their usage on sites that charge for access to their app. So while you can download these apps for free, you cannot use them.
It’s not really anyone’s fault, since the lack of support is the fault of the programmers. The fact is that these apps are only downloaded by people who want to get something for nothing. Other reasons why they download are obvious. Some people download these apps just to annoy other people. What do you expect from a paid app? You are downloading something just to annoy someone, which is obviously not what you signed up for. If this is your reason why you downloaded it, you will be glad you know it by now.
For those who download and use the paid apps, they are usually offered a chance to download the free versions in exchange for their names. There are even times when they will pay you for sharing the app with others, although this isn’t really known to most people. That’s the reason why many will use top Android apps as an investment in themselves.