The platform is designed to provide video content grouped around themes of Culture, Wellness, Home & Family, Food, the Mind, and Entertainment.
Wonder is backed by $1.3m of financing from Universal Music, former Apple EMEA CEO Pascal Cagni, VICE Media and Qualcomm.
Surname & Surname won the work through a competitive pitch and will support Wonder with a planned PR-focused campaign to drive word of mouth and increase downloads. There was no incumbent agency.
The agency will report to Wonder founder and CEO Sofia Fenichell, who said the agency was selected because of its work with YPlan and Hailo and its experience of combining traditional PR with digital campaigning.
She said: "Wonder has been created to deliver a professional video platform for content creators that both makes good business sense and provides an enjoyable experience for consumers. If YouTube is Walmart, we want to become the Whole Foods of video and we know Surname can help us achieve that goal."