App Profile: Flash Tree

Flash Tree is like having a synced countdown in your pocket. No more having to ask someone to start a race. Just select your preferred countdown, hit start, and GO! You can sync multiple devices to the same countdown for a group race.

Flash Tree has 2 payment options

Free: You can join any race invited by others for free
Paid: The app asks for $1.99/month subscription to start race and invite others.

Terms of Use: https://www.apple.com/legal/internet-services/itunes/dev/stdeula/