How free apps on the store make money

Well, I write this because yesterday I got a broadcast about how to get money by installing free apps. Telling us that free apps get money from google for every installation. Well, I can say that it is bullshit and totally a scam, of course.

But, when I tell my friend it is a scam, it leave a question mark on him. "How free apps on the play/app store make money?". Well, there are some reason why developer publish their apps for free.

1. It is a non profit app
       Not very app on the store are profit oriented, some of them made by non profit organization, to help human being. Well, you can say they are the real MVP.

2. It is a free apps with ads


      Sometimes when you install free apps, there will be some ads displayed on the content. the developer will get paid if we click the advertisement, or for large view count. Google itself has an ads provider for apps developer named admob. And there are several more ads provider like charboost, unityads, and so on.

3. It has in app purchase


         I cant find an easy way to explain in app purchase. But shortly, you can get the apps for free, but the apps developer sell items inside the apps. For example, game sometimes have virtual money, and you can upgrade your character with that, become more powerful. you can get the virtual money by completing quest, or paid with real money (the fast way). and that's how the developer get their money.

to be honest, now mobile users are rarely paid for an apps. that's why now developer choose in app purchase for their revenue source. waiting users to be addicted to their apps and easily spend money there.

ok, that's all for today. hope this article can enlighten many peoples about free apps business. 
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