Every September, Apple releases a major iOS update. Every fall, Google releases a major Android version. And every year, development teams who did not prepare scramble to fix compatibility issues while their users flood the app store with one-star reviews about crashes and broken features. The cycle is entirely predictable, which makes the teams who are caught off guard every single year particularly frustrating to observe.
Major OS updates are not surprises. Apple and Google both announce them months in advance, provide developer betas starting in early summer, and publish detailed migration guides documenting every change that might affect existing apps. The information is available. The timeline is known. The only variable is whether your team uses that lead time to prepare or wastes it hoping nothing will break.
The Preparation Timeline
When Apple or Google announces a major OS version at their developer conference, typically in June, download the beta immediately and install it on a dedicated test device. Run your app through its critical user flows and note any issues. Do not fix them yet because beta releases change frequently, but document what you find so your team has early visibility into the scope of work ahead.
As the beta releases stabilize over the summer, begin addressing the issues you identified. Prioritize changes that affect core functionality and user-facing experience. Cosmetic issues and optimization can wait for a follow-up release. The goal is having a compatible update ready for App Store or Play Store submission before the public OS release in September.
Test again with the release candidate beta, typically available a week or two before the public launch. This is your final verification pass. Submit your updated app to the stores before the public OS release so that users who upgrade on day one find a compatible version of your app waiting for them.
Common Breaking Changes to Watch For
Permission model changes are the most frequent source of post-update crashes. New OS versions often add new permission requirements or change how existing permissions are requested and granted. An app that previously accessed location data without explicit permission may crash when the new OS enforces a permission prompt the app was not designed to handle.
UI framework changes affect how views render, how animations behave, and how navigation transitions work. What looked correct on the previous OS version might display incorrectly or animate strangely on the new one. These visual regressions do not crash the app but they make it look unprofessional and erode user confidence.
Deprecated API removals happen gradually. Apple and Google deprecate APIs in one release and remove them entirely in a subsequent release. If your app uses deprecated APIs that are finally removed, the affected functionality simply stops working, often without a helpful error message.
Building OS Update Resilience
Design your app with change in mind. Isolate platform-specific code behind abstraction layers so that OS-specific changes affect a small, well-defined area of your codebase rather than rippling throughout the entire application. Use recommended platform APIs rather than undocumented behaviors that might change without notice.
A maintenance team that prepares for OS updates as a standard part of their annual cycle ensures your app transitions smoothly through platform changes rather than breaking during the most visible moment, when your users are excited about their new OS and paying close attention to how their apps handle the upgrade. For more on maintaining reliable mobile apps, visit our blog.
