How can this project be widely known? Because most of the tourists travel through travel companies and OTA's are already covering most of the travel industry?
As per my knowledge and experience, Social media would be the best platform for the marketing of the Goeureka services as most of OTA's are currently using Social media only as they cover almost everyone one way or another.
As ICO is still on for Goeureka they might be able to gather enough attention from the investors to make this project a huge success.
Not only marketing through Social Media but hotels partnering with Goeureka will also be indulged in marketing for their own benefits as they will be making profits through this Goeureka platform. Re-targeting the existing customers will play a important role to retain them.