Created in early 2012 and backed by the investors behind Zoopla and Spotify, the app offers users easy access to London events at the last minute.
Having already generated buzz in the tech press, Surname & Surname has been briefed to handle consumer activity to attract consumers to use the app.
YPlan marketing director Rachael Tasker said: ‘We have very ambitious plans for the future and are excited about working with Surname & Surname on creative and commercial consumer campaigns that will generate great results for our brand.’
The start-up gained seed-stage funding of £1.06m and widespread attention when Stephen Fry tweeted his love for the app to more than five million of his followers.
Yplan's backers include the investment firm behind keyboard app SwiftKey, as well as Lastminute.com co-founder Brent Hoberman and Robert Linney, co-manager of The Chemical Brothers.