Make a Mobile Game With AI: Try It on Your Phone Early

To make a mobile game with AI, design for one thumb and open the game on your real phone from the very first day. Start it as a web page your phone can load, and think about app stores only once the game is fun.

What changes when a thumb is the controller?

Nearly everything your AI assumes by default. Its first idea of a game has a keyboard, a mouse and a big screen. A phone has none of these, and it brings problems of its own:

• Your thumb hides the action. Whatever sits under it is invisible.
• There is no hover. Nothing can react to a pointer resting over it.
• Reach is limited. In one hand, the top of a tall phone is a long way off.
• Play gets interrupted. A call, a message or a closed app can end a round at any second.

Picture a game about a heron at the edge of a lake. Hold your thumb down and the heron leans over the water. Let go and it strikes. That is the whole control scheme, and it works on a bus, standing up, with a bag in the other hand. Good phone games tend to be built around one gesture that simple.

Buttons need room too. W3C's accessibility rules set out a target of at least 44 by 44 CSS pixels, because small targets are hard to hit with coarse touch. Treat that as a floor.

How do you start?

Ask for a web page that your phone can open, and leave stores for later. You will change things every few minutes in the early days, and reloading a page is far quicker than installing an app.

1. The one-thumb action, on your real phone.
2. A round short enough to fit between two bus stops.
3. Small and large screens, in one fixed direction.
4. Interruptions: pause, save, and come back exactly where you were.
5. Sound that is pleasant, and a game that still works with sound off.
6. Only now, wrapping it as an app.

What do the app stores ask for?

Each store has its own costs and steps. Apple's enrolment page gives the Apple Developer Program as 99 USD per membership year. Google's help pages list a one-time registration fee of US$25, and they say that personal developer accounts created after 13 November 2023 must run a closed test with at least 12 testers, opted in continuously for at least 14 days. These details come from their pages on 2 November 2026, and they can change. Plan for two weeks with twelve real people, because you cannot rush that part.

What is the mistake that wrecks phone games?

Building for weeks on a laptop with a mouse. Everything feels fine, because a mouse is precise and your screen is huge. On the phone, your finger covers the heron, the buttons are too small and the text is unreadable, and you are redoing the foundations.

Paste this to your AI

Build a small mobile game as a web page I can open on my phone: played with one thumb, upright. Tell me exactly how to open it on my phone.

Before the game, draw a session as a state machine in a Mermaid diagram: open, playing, paused, interrupted by a call or another app, back again, round over, play again. For each state, say what is saved. Build from that.

Every button is at least 44 by 44 CSS pixels, and nothing important sits under my thumb.

You cannot hold a phone, so never tell me the controls feel right. Tell me which screen sizes you tried and what you saw on each. For anything you could not try on a real phone, say you do not know.

Or skip this and connect the MCP: your AI then finds all of this by itself.Connect the MCP

How to check it worked

• Play standing up. One hand, on the move. A bus is ideal.
• Take a call. Ask someone to ring you in the middle of a round.
• Switch apps and come back. You should be exactly where you left off.
• Turn the phone sideways. The game should cope, or stay put on purpose.
• Borrow a small phone. Nothing should be cut off.
• Play on silent. You should lose nothing you need.