A small set of useful apps can make a first trip to India much easier. Start with a maps app for navigation, a taxi app for local rides, the official railway booking app for trains, and city-specific metro apps when you plan to use urban transit.
Food delivery apps can help after a long travel day, while grocery delivery apps are useful for water, snacks, and daily essentials in supported cities. It is also smart to save emergency numbers and hotel details before you begin travelling.
The best setup is not the largest number of apps. It is a simple mix that covers the places you will actually visit: transport, maps, food, bookings, and emergency help.