Screen rules
Twelve rules for composing a DayTwo screen. Components keep parts consistent; these rules keep whole screens usable. Every one is tied to a user outcome — if a choice doesn't serve one of these, reconsider it.
1
One screen = one job
A first-time user can hold one task at a time. One job per screen removes the "what am I even doing here?" moment.
2
One primary action per screen
The eye looks for the single brightest thing to tap. Exactly one primary action turns that instinct into the right action.
3
Use concrete language
"Record sale" beats "Submit". Concrete words tell a non-technical user exactly what will happen.
4
Avoid accounting jargon
Terms like "gross revenue" or "reconcile" exclude the user. Plain words keep the shop owner in control of their own numbers.
5
Show the smallest next step
Big asks stall people. The smallest next step keeps momentum and builds the capture habit the advice depends on.
6
Make the system state obvious
Saved? Syncing? Offline? When state is visible, the user trusts the app instead of guessing.
7
Show recovery paths when something fails
Failures happen on poor connections. A clear way back ("Retry") keeps an error from becoming a dead end.
8
Do not hide important edge cases
A "cleaner" screen that drops the offline or error path isn't cleaner — it's broken exactly when it matters most.
9
Design for first-time users without a trainer
There is no one beside the user. If a screen needs explaining, it isn't done.
10
Design for low-end Android
Heavy screens drop frames on cheap phones and feel broken. Lightweight UI keeps the app usable for the people we serve.
11
Design for users who may be offline
Connectivity is intermittent. Capture must work offline and sync later — never block the user.
12
Design for Burmese and English text expansion
Burmese runs ~1.3–1.7× longer. A layout that only fits English breaks for half the users.
How to use these
Treat them as a checklist when designing or reviewing a screen, not as decoration. Most usability problems in DayTwo trace back to breaking one of them — usually one primary action, an unhandled edge state, or a layout that assumed English length.
Every rule earns its place by a user outcome
These aren't style preferences. Each one improves comprehension, confidence, speed, error prevention, or recovery for a first-time shop owner using the screen without help. That's the bar.