The Spring Developer Challenge by Platform Week encourages developers to create real-time, collaborative applications using Cloudflare's tools. These include Workers, Worktop, Pages, Durable Objects, Workers KV, and R2. Participants can merge their ideas with newly released features, earn recognition on the blog, and receive swag. The challenge is open to developers aged 18 or above, who can work in teams of up to 10 people. Submissions are due by May 24 June 7, and participants can seek help via Discord.