Vedantu at The Kranky Geek WebRTC!

If you follow us on our social channels, you must be aware that recently Vedantu took part and showcased its work in WebRTC technology in The Kranky Geek WebRTC event held in Bangalore.

At Vedantu, we use WebRTC to power the LIVE sessions between a teacher and a student. This is a powerful technology that’s shaping up to change the way we connect with each other online. Our goal is to provide a seamless and immersive learning experience to the students at Vedantu and connect them at scale with the teachers. We started with the p2p model of WebRTC, that connects a teacher to a student, learnt a lot scaling it up and operating under fluctuating network conditions in India. We are now experimenting with MediaServer to power our 1-to-few model where a small group of students learns from a teacher in the utmost personalized way.

As the WebRTC landscape continues to evolve, it can be hard for developers to keep up with the pace.  The Kranky Geek WebRTC event aims to fill in the gaps and jump-start the knowledge about WebRTC and the ever-changing landscape of communications online. In this talk at Kranky Geek, we shared our journey at Vedantu in building an online educational platform using WebRTC. Here’s Vedantu’s presentation in the event for you all to have a look –

Also, here is the video presentation by Vedantu –

Poor Man’s Stylus

Touchscreens have become ubiquitous interfaces. There are absolutely no barriers for using touch gestures to get things done on smartphones, tablets or any other smart devices. Even toddlers seem to quickly grasp the concepts of ‘swipe’, ‘drag’ and ‘pinch zoom’ with minimal instructions. In fact, I  have seen most of the toddlers trying ‘swipe’ on everything they interact with these days.

As with any technology, the ubiquity of use doesn’t necessarily mean the ubiquity of knowledge on how the technology works. Though people use smartphones and interact with the touchscreens many times a day, the know-how of what happens underneath our fingers still remains a mystery to many.

Here at Vedantu, when we ventured into building the entire experience of teaching and learning on a smartphone, we realized how amazing the technology is. The sheer amount of possibilities the smartphones open up for innovation blew our minds. After months of fun-filled experimentation, we have fully-functional whiteboard on smartphones and tablets running on Android. Students can continue their learning on devices which they grew up having fun with.

One of the biggest challenges we encountered while building whiteboard technology was to differentiate between the touch of a finger and that of the palm resting on the touchscreen. The challenge was more pertinent in case of tablets where the sensitive touchscreen is larger or when users prefer to use a stylus to write on the touchscreen.

We thought of researching on understanding the user experience around using stylus on Vedantu whiteboard on tablets. While we were doing so, on a weekend, I didn’t have a stylus to work with and started researching how exactly a stylus work with a touchscreen. I realized, almost every smartphone in present day’s market sports some form of capacitive touchscreen, which has an electrostatic grid above the display screen. When the user taps on this screen, charge from this grid is discharged through the skin of the finger. And that’s the simple yet powerful mechanism that detects touch on the device – Making the world go round on the fingertips!


Now, after knowing the fact, I couldn’t stop my curious mind from digging deeper into details and researching about materials that can discharge the static charge from the touchscreen to simulate a finger touch. The easiest find was a piece of an aluminum foil used to wrap food in order to retain heat. I folded a small piece of foil and wrapped it around the pen and started using it, just like one would use a pen – My test stylus was ready!

I tapped on the phone and voila, it worked! The touchscreen was tricked to process it as a touch event!

Though I could navigate, writing on whiteboard was not satisfying.  So, the curious mind got to the work again – The hunt for best materials to be used for refining the writing experience while tricking the touchscreen.  I tried tin used for soldering, copper wires, capacitors from my college lab kit, metal enclosure of dead mobile batteries and whatnot! Finally found a material that was deceptively simple and ubiquitously used in packaging – Anti-static plastic! (Yeah, I actually spent quite some time before discovering something as abundantly available as this) This is the same plastic used for wrapping most of your gadgets and appliances, especially hard disks, motherboards, etc. Yes, there is a reason behind using it, this plastic discharges static current created in such gadgets/parts through friction.

The excited me, couldn’t control myself from quickly building up a prototype. I ran around the office showing off my poor man’s stylus to my fellow Vedans (yeah, that kinda gave me a high and I was enjoying my very own Eureka moment). Later sometime, while surfing the Internet, I realized that I was not the only one hacking up styli from such mundane materials. This boosted my ‘hacking spirit’ a few counts high and I couldn’t stop myself from sharing the excitement with you all through this wonderful medium provided by Vedantu – Awesome place for innovations!

I am sure a lot of you might be having your own hacking stories, do share them in the comments below, I, errr…we would love to read them 😛
About the Author


Supreeth works with Vedantu as an Android Engineer and enjoy watching world cinema apart from diving deep in such crazy hacking!