Ad Block

Downloads: More than 10 million
Launch date: After 2006
Ad Block is the most widely used browser extension out there. It blocks all ads on a webpage and can even extend to YouTube, blocking advertisements that precede videos. This extension is not Indian but was among the first to catch on here.
Compare Hatke

Downloads: 9,723
Launch date: July 2012
With this extension, you no longer have to visit different e-commerce websites, such as Amazon and Flipkart, in order to compare prices of a product. It will help you compare prices offered by 10 portals.
CouponRani

Downloads: 376
Launch date: July 2012
This extension offers coupons and deals, free of cost, and then delivers them in the same browser tab. The number of people who have downloaded CouponRani may be modest, given how long ago it was launched, but it is among the extensions trending in the Chrome store in India.
Hola and ZenMate

Downloads: 5,095,141 and 1,804,506
Launch dates: September 2012 and May 2014
Hola Better Internet and ZenMate Security & Privacy VPN are free virtual private networks. These extensions were not developed in India but are hugely popular among Indians. They allow the user to take on another internet protocol, or IP, address. This allows people to appear to be surfing from a foreign country instead of their own. People mostly use these extensions used to connect to websites blocked in India. Many youngsters use them to connect to Netflix, a video streaming website, to watch television shows they cannot otherwise access from India.
PNR Status

Downloads: 15
Launch date: December 2014
In December, a Reddit user, surjithctly, wrote a post about a Chrome extension that he had created. Called PNR Status, it allows you to find out the status of their railway tickets without requiring them to visit the Indian Railways website, which many find slow. All you have to do is type 'PNR Status' in Google search and a widget will show up. You have to type the PNR, or passenger name record, number into the widget, and the status of the ticket will get displayed.