Some engineering decisions are reversible with a refactor. Others follow you forever. The on-device data schema every future version must migrate against, the API contract three-year-old clients still depend on, the push notification architecture, the minimum-version floor, the persisted state format. Mobile is uniquely unforgiving here.
This talk maps the one-way doors of iOS development.Which decisions are truly irreversible, why they're so easy to walk through casually,and what they cost once you have millions of installs in the wild.
So how to recognize a one-way door before committing, when irreversible decisions deserve slow deliberation versus when speed win and the versioning and abstraction techniques that convert one-way doors into two-way doors.