How do I get Darren to build something? Tell Tycoon Agent the outcome you want. Tycoon Agent creates a Task, and Darren carries out the work. You can track progress, see evidence, and review the final deliverable on that Task.
Does Darren do mobile? Yes, for mobile-friendly web apps and Progressive Web Apps. Native iOS/Android binaries are not in scope today.
What doesn't Darren build? Darren doesn't build hardware firmware or native game engines. Anything needing manual platform certification, like App Store reviews, is on you — Darren can write the code, but you handle the certification process. Every shipped project comes with a live URL.
For what skills are, see skills.