I find pagalguy app , a very informative and easy to use app. This app have a group of people sharing information about a particular topic.
For example: ; you are preparing of GATE or bank or any competitive exams then on pagalguy you can simply join these particular groups and discuss any query regarding exam with other aspirants preparing same exam as you are.
Here you will be interacting with many peoples sharing their own thoughts on topic or upcoming exam.
Moreover after taking any exam you can discuss questions among pool of students.
So in my opinion pagalguy is must to download app.
Cheers up.