Gratitude is an app which works out how much of a tip you give to waiting staff, taxi drivers, bar staff and hotel staff across the world. Its clever algorithm uses your location and level of service received to accurately tip based on the country you’re in and the bill amount. No need to calculate it yourself! We live in a fast-paced world of international travel and cultures. Do you find yourself constantly confused about how much of a tip to leave and reaching for your mobile’s calculator? What happens when you need to split the bill between a group of you here or abroad?