The problem Bachao solves

Our hack aims at solving a very key problem: Safety.
At its core, our app provides your location to emergency contacts via SMS and call alert in case of any situation which may require so.
Now, while this has been an oft taken up idea, there's still a lot missing from even the best implementations of today. We aim to solve the following core challenges.

Challenge #1: Automatic sending of the messages: While you may be able to open the app and tap the Distress button yourself in some cases, in many, you'll not. This is possible in cases of accidents, where you may be rendered unconscious. In this case, using no other hardware than your smartphone sensors, our app will figure out you need it, and generate a prompt. If you do not cancel this within a given time, the message will be delivered autonomously. Checks will be put in place so that the signal is not erroneously triggered after consulting data and papers on car crashes.

Challenge#2: It would be very optimistic of us to assume that you will have network when you need to send a distress signal. But sometimes, it’s not the case, and you are left with no options to relay your distress. The solution we propose here is a novel one and has not been thought of in this domain yet, ULTRASONICS.
In the possible medium of communication without cellular network, ultrasonics are a newly emerging media, which trump NFC, Bluetooth and Infrared in terms of range and penetration. We intend to encode your geolocation via sound and send it to receivers nearby, informing them, all without a mobile network. This, according to us, adds another layer of safety to the person, giving him or her a chance at help even in the remotest of places.

Challenges we ran into

The major challenge we faced was figuring out a way to communicate without a cellular network. In trying to find an existing one, we found bluetooth and other substitutes, which did not satisfy our expectations. We brainstormed and came across the idea of sending radio signals, only to find out it isn't possible to do so without custom hardware.
With a stroke of inspiration, we thought of the most basic thing a phone has, speakers and microphone, the 'Originals'. With the little physics we remembered from our JEE days, we figured that ultrasound has the highest reach that a mobile phone can provide.
We found approval of our idea in the most unexpected place possible, in the world of Payments. Google pay uses ultrasounds to make payments, a credit to the robustness and secure nature of this.