Is it possible to make an app/create an app count using aadhaar card details?

I am planning to make an android app which uses aadhaar card number to create an account. Using this way, fake accounts will be minimized or even stopped! But my question now, is it possible to do this in such a way? or Does the government keeps all the details as private? If so, then why such apps like mobikwik, paytm, idea app, etc asking to link account with aadhaar card?

Yes its possible. Aadhaar details are public but a paid service. Aadhaar bridge is what it is called. It has 2 type of accounts, developer account which costs 5000 for 2 months and Enterprise account which is charged for usage. Like you said all companies like mobikwik ,paytm etc are clients of this.

For more details go through this link.

https://www.aadhaarbridge.com/pricing.html

They provide SDKs for implementing AUTH and e signing