Answer : 1. "रक्षा मंत्रालय"
Explanation :

Ministry of Defence launched a mobile app 'RDP India 2019' on 26 January 2019. The aim of the app is to show the highlights of the Republic Day event, not only to the spectators at Rajpath, New Delhi but also to the general public all over the world. This app contains information about the Parade on Rajpath, New Delhi, including Order of the March, details of the tableaux presented etc.