How to Fix an App That Crashes After an iOS Update
Why a new iOS version can suddenly break your app, what to do about it immediately, and how to stop it happening again.
Short answer
An app that crashes after an iOS update usually broke because it was not maintained: a new iOS version changed or removed something the old code relied on. The fix is a developer diagnosing the crash, updating the code for the new iOS, testing, and resubmitting to the App Store. If your original developer is gone, secure your code and Apple account, then bring in a team to fix it. The real cure is ongoing maintenance. For the wider picture, see our guide on what app maintenance costs after launch.
Why iOS updates break apps
It feels unfair: your app worked fine, you changed nothing, and then a new iPhone update arrived and it started crashing. But the cause is straightforward once you understand it. Apple releases a major new version of iOS every year, and each version changes how some things work under the hood, and occasionally removes older ways of doing things entirely. An app is built against the iOS of its time, and if it uses something Apple later changes or retires, that part of the app can break when users move to the new version.
The crucial point is that this does not happen to apps that are kept current. Maintained apps are updated to match each new iOS, so they keep working. It is the apps that were built and then left untouched, no updates, no one watching, that suddenly break, because the world moved and they did not. Your crash is not random bad luck; it is the accumulated result of an app falling behind iOS. That is why the same update breaks neglected apps while well-maintained ones sail through, and it is also the clue to the real fix.
What to do right now
If your app is crashing on the latest iOS and users are leaving one-star reviews, the priority is to act quickly, because every day the broken app stays live costs you users and damages your rating. Move in this order.
- Confirm and assess the damage. Check how badly it is broken, on which devices, and read the reviews to see what users are hitting, so you can brief a developer clearly.
- Make sure you control your code and account. You will need access to your source code, your Apple Developer account, and any backend for anyone to fix the app. Confirm you have these now.
- Get a developer on it fast. Bring in a competent developer or team to diagnose and fix the crash, whether your original one or a new one if they are unavailable.
- Communicate if you can. A brief, honest note in your reviews or support channel that a fix is coming can slow the bleeding while it is being worked on.
Speed matters here more than perfection. A live app crashing for every user is an emergency, and the goal of the first hours is to get someone qualified diagnosing it and to make sure nothing, like access to your own code, is blocking the fix.
How the fix actually works
Fixing a crash from an iOS update is usually a focused repair, not a rebuild, provided the underlying code is sound. The process a good developer follows is methodical. First they diagnose the exact cause: crash reports and testing on the new iOS pinpoint what broke, often a specific feature or piece of code that the update changed. Then they update that code so it works correctly with the new iOS, using the current, supported way of doing what the old code did, ideally in native Swift.
Next comes thorough testing on current devices and iOS versions, to confirm the crash is gone and nothing else broke in the process. Finally, the fixed version is resubmitted to the App Store, where it goes through Apple’s App Store Review Guidelines again, usually a quick re-review of about a day, before it reaches users. In many cases the whole repair takes days rather than weeks, plus the review time. The main thing that slows it down is not the iOS change itself but the state of the existing code: clean code is quick to fix, while a tangled, poorly built app makes even a small fix slow and risky, which is worth knowing before you assume the worst or the best.
Why it happened: the unmaintained app
| Maintained app | Unmaintained app |
|---|---|
| Updated with each iOS version | Left untouched after launch |
| Tested against new iOS early | Discovers breakage from user reviews |
| Rarely crashes on updates | Breaks when iOS changes underneath it |
| Small, ongoing cost | Sudden emergency and lost users |
The table gets to the root of the problem. An app is not a finished object that stays working forever; it is a living product in a moving environment, and iOS moves every year. The apps that break after updates are the ones no one was maintaining, so they fell behind until a change finally caught them. This is almost always the underlying story behind a post-update crash: not a freak event, but a predictable consequence of an app being left alone. Understanding this reframes the fix, because the crash is a symptom, and the disease is the lack of maintenance.
If your original developer is gone
A painfully common version of this situation is that the app broke and the freelancer or developer who built it has vanished, leaving you with a crashing app and no one who knows the code. It feels hopeless, but it usually is not, as long as you can get to your own assets.
The key is access. If you own or can reach your source code, your Apple Developer account, and any backend, a new competent developer can take over, understand the code, and fix the crash, even without the original author. So the first move is to secure those things, exactly as you would when changing developers deliberately. If some of them are locked in a departed developer’s accounts, retrieving them becomes the urgent first step. Our guide on changing app developers mid project covers how to secure your assets and hand over safely, and the same principles apply to rescuing a broken, abandoned app. The reassuring truth is that a disappeared developer is a serious inconvenience, not the end of your app, provided you control what is yours.
Preventing it next time: maintenance
| Your situation | Sensible approach | Why |
|---|---|---|
| App is live and matters | Ongoing maintenance plan | Keeps it current with each iOS |
| Between developers | Secure code, then arrange upkeep | No one is watching the app otherwise |
| Tight budget | At least test before each major iOS | Catch breakage before users do |
| Business-critical app | Proactive maintenance and monitoring | Downtime is lost revenue and trust |
The honest lesson from a post-update crash is that the real fix is not the one-time repair but preventing the next one, and that means maintenance. A maintained app has someone keeping it current with each iOS version, ideally testing against new versions before they reach the public, so the crash never happens where users can see it. Maintenance is a modest ongoing cost, usually a fraction of the build per year, and it is far cheaper than the emergency repairs, lost users, and damaged reviews that come from letting an app drift. Treating maintenance as optional is exactly what leads to the crash you are now fixing.
Apple also forces the issue on a calendar now. Its upcoming requirements page states that since April 28, 2026, any app update uploaded to App Store Connect must be built with Xcode 26 and the iOS 26 SDK. An app that has drifted for years cannot just receive a one-line patch: the fix has to compile cleanly against the current SDK before Apple will even accept it, which is one more reason the cheap option is keeping the app current rather than rescuing it.
When the fix is bigger than a patch
Be realistic that sometimes a post-update crash reveals a deeper problem. If the app was built cheaply or badly, the update may have exposed code that is fragile throughout, not broken in just one place, and in that case a quick patch may not hold, with the next iOS update likely to break something else. A developer assessing the app will tell you honestly whether this is a focused fix or a sign that parts need rebuilding properly. That is not the common case, most update crashes are specific and fixable, but it is worth knowing so you are not surprised if the assessment is bigger than hoped.
Either way, the path forward is the same: get a competent team to diagnose the app, fix what is broken, and then keep it maintained so it does not happen again. A team that designs and builds under one roof, as we do, can rescue a crashing app, get it working on the current iOS and back through Apple’s review, and keep it current afterward, with you in control of your code and Apple Developer Program account throughout. See examples in our work and get your broken app looked at quickly at a short call.
FAQ
Why does my app crash after an iOS update?
Because a new iOS version changed or removed something your app's code depended on, and an unmaintained app was not updated to match. Apple releases a major iOS version every year, and older code that used features Apple has since changed or retired can suddenly break. The crash is a sign the app fell behind iOS, which is why apps that are actively maintained rarely have this problem.
How do I fix an app that crashes after an iOS update?
Have a developer diagnose the exact cause, update the code so it works with the new iOS, test it thoroughly on current devices, and resubmit the fixed version to the App Store. It is usually a focused fix rather than a rebuild, if the underlying code is sound. The key is acting quickly, because every day the broken app stays live costs you users and reviews.
What do I do if my app developer disappeared?
First secure what is yours: get access to your source code, your Apple Developer account, and any backend, because you need these for anyone to fix the app. Then bring in a new team to diagnose and repair the crash. As long as you own or can access your code and account, a competent developer can fix a broken app even if the original one is unreachable.
How long does it take to fix an iOS update crash?
Often days rather than weeks, if the code is sound and the cause is a specific iOS change, plus the time for Apple to review the resubmission, usually about a day. A tangled or poorly built app can take longer, because the fix is harder to make safely. The biggest variable is the state of the existing code, which a developer can assess quickly.
How do I stop my app breaking after future iOS updates?
Maintain it. Budget for ongoing maintenance so a developer keeps the app current with each iOS version, ideally testing against new versions before they reach users. Apps break after iOS updates almost entirely because no one is maintaining them; a maintained app is updated ahead of or alongside iOS changes, so users never see the crash in the first place.