The whole category in one page.
A DEFECT SHIPPED PERSISTS ON DEVICES FOR MONTHS
Users do not update immediately and some never do. That single fact drives staged rollouts, remote feature flags, backward-compatible APIs, and care before release.
THE SYSTEM CAN TERMINATE YOUR APPLICATION AT ANY MOMENT
Save state as it changes, restore position on return, and never lose what the user entered. That is what they notice.
TEST ON A MODEST PHYSICAL DEVICE
Emulators and development hardware conceal performance, battery use, data consumption and real network conditions — which are exactly what matters in this market.
THE CLIENT CANNOT BE TRUSTED
Every authorisation decision belongs on the server, and anything embedded in the binary is extractable. Obfuscation is delay, not protection.
TREAT OFFLINE AS A NORMAL STATE
Read from local storage and let the network update it. The interface then never waits, and works offline by construction.
SIZE AND DATA ARE COSTS THE USER PAYS
Download size determines whether people install at all, and every byte transferred is paid for.
REQUEST PERMISSIONS AT THE MOMENT OF USE, WITH CONTEXT
And design for refusal, because it happens.
KEEP STORE DECLARATIONS ACCURATE AND YOUR SIGNING KEYS SAFE
Those two failures are unrecoverable in ways that ordinary defects are not.
