Passengers can invite friends to share their referral code to a friend via email, SMS or any social media including Facebook, Twitter, and Whatsapp. The respective amount will be credited to the friends’ wallet, which can be used for payment for the rides they undertake. (For instance, if the referral amount is $20, when passenger 1 shares the referral code to passenger 2, the wallet of passenger 2 will be credited with $20. When passenger 2 completes the ride using the provided referral code, $20 will be credited to the wallet of passenger 1.) Thus, users at both ends gain benefits.