My Newest App Feature Cost Less Than a Cup of Coffee
2026-05-20
My newest app feature cost less than a cup of coffee.
The idea happened completely by accident.
I was out in the barn with my daughter practicing.
We accidentally created a 4-second video lag on the projector while recording.
She could watch herself in delayed real-time without touching the phone.
Zero control or interaction with the device.
Rep after rep, she could self-correct by glancing at the wall.
$1.50
Total cost to build and deploy
That accidental lag is now Mirror Mode in Player 1 Training.
Instant replay without stopping the session.
I built and deployed it with an AI coding agent.
BUILD RECEIPT
AI coding agent (Pi)$0.80
Inference / tokens$0.45
Deployment$0.25
TOTAL$1.50
Less than a cup of coffee. Shipping in production.
— Jon