mAadhaar has been launched by the UIDAI and it has been done in order to make uses of Aadhaar card easy. Aadhaar card is the most recognized way for identifying that you are a citizen of India and government has made t mandatory for many purposes, like property registration. With mAadhaar it is going to be easy to share details with the third parties.
What mAadhaar app does, whats is its purpose:
Once you set up the mAadhaar app in your Mobile including your phone number, address and other details. This app makes it easier for the third party, external users to download your details. Its a pure responsibility of the user to share their details with anyone which this app will make it very easy to use.
For example in case you are buying a SIM card for a new phone connection then this App is going to make very easy for your provider to take down your details. So mAadhaar will make it very easy to share your information with the third parties.