Earning through an application is still a good idea or not

Hey guys just want to discuss something about android application and it's earning.

I have an idea and it's related youth niche and it will be a boom if that application have facebook app and android app both.

I was thinking about to create it by myself because it's not too complex the logic is super easy and simple to code all I have to do designing and I can manage it.


** Any comments regarding facebook application as a game or a wall post app**
*** The app which posts a image on your profile with some junk**
That works I guess and please let me know if I'm thinking wrong.

Will promote some advertisements regarding app on insta and fb which will generate some leads of downloads.

Please let me know your suggestions going to start work on it soon
If I'm wrong let me know guys

Thanks

Do people still code desktop apps for windows and mac? Those could earn too since people still use those. I personally hate running apps on a tiny phone why would I not use a widescreen for my apps and my browsing. What's the matter with people today?

I am talking about android apk and facebook (web app)application