3. Jambool

Founder: Vikas Gupta, ex-Head of Payments and Web Services Groups

Founded by ex-Amazon head of Payments, Vikas Gupta, Jambool was an ecommerce company which operated Social Gold, a virtual goods monetization platform. He also was lead inventor for Amazon’s Flexible Payments Service.

The company enables developers to create and manage their own virtual currency, to provide an in-app payments experience to their users, and analytics to monitor their virtual economy. It powered the virtual currency and payment solutions for thousands of online games and virtual worlds. It was among the top 10 application developers in 2008.

Google acquired the company in August 2010 and it is now known as Google Wallet.

2. Vittana

Founder: Kushal Chakrabarti, ex- Technical Lead

CEO of Vittana, Kushal was responsible for technical strategy and development of the Amazon.com personalized recommendations engine. The author of over patents, papers and talks under Amazon, founded Vittana on a gut feeling in 2007.