CompTIA A+ Core 2

iPhone and Android app crashes: A+ Core 2 troubleshooting order

Work from least to most disruptive. On iPhone: force close the app, restart, check for an app update then an iOS update, and only then delete and redownload the app, which can lose its data. On Android: restart and update, force stop, clear cache and data, then uninstall. If one app still fails while others work, contact its developer.

iPhone: the order of steps

Apple's steps for an app that stops responding, closes unexpectedly or will not open are: force the app to close and reopen it; restart the device; check the App Store for an app update, and if there is none, update iOS; then delete the app and redownload it.

Deleting comes last because you might lose data stored in the app. If the app came from the App Store and still fails, contact the app developer.

Force closing is for an app that is not responding. Apple notes that force closing apps unnecessarily can slow the device, because a closed app takes longer to reopen while it reloads its data.

For a slow iPhone, Apple also suggests keeping at least 1 GB of storage free, turning off Low Power Mode, keeping the phone at a moderate temperature, and checking battery health.

Android: the order of steps

Google's steps for an app that crashes, will not open or will not respond are: restart the phone and update Android and the app; force stop the app; clear the app's cache and data; then uninstall it, which erases its data. Restart after each step to check whether it worked.

Then decide who to contact. If only one app has trouble while others work, contact the app developer. If no apps will update or Google apps fail, contact Google Play.

If the phone itself restarts, freezes, crashes or runs slowly, restart it in safe mode. If the problem goes away there, an app is likely the cause. Restart normally, then remove recently downloaded apps one at a time, restarting after each removal.

Apps from outside the official store

Google Play Protect checks apps from the Play Store before download and checks the device for potentially harmful apps from other sources. If it finds one, it may send a notification (tap it, then tap Uninstall), disable the app until it is uninstalled, or remove it automatically. Google recommends always keeping Play Protect on.

Signs of a jailbroken iPhone

Apple lists the effects of unauthorized modification of iOS (jailbreaking): security vulnerabilities; instability, with crashes and freezes of built-in and third-party apps and data loss; shortened battery life; dropped calls and unreliable data; and disruption of services such as iCloud, iMessage, FaceTime and Apple Pay. Some modifications can make the iPhone permanently inoperable after a future iOS update.

Worked example: a secondhand iPhone whose built-in apps crash, whose battery drains fast, and whose Apple Pay and iMessage have stopped working shows the pattern Apple describes for a jailbroken phone.

Jailbreaking violates the iOS and iPadOS Software License Agreement, so Apple may deny service for an iPhone with unauthorized software installed.

Where the exam catches people

Believing deleting and reinstalling is the first fix on iPhone: it comes after force close, restart and updates because it can lose app data.
Believing force closing every app keeps an iPhone fast: Apple says unnecessary force closing slows the device.
Believing a factory reset is the next step when an Android app freezes: force stop, clearing cache and data, and uninstalling come first.
Believing Google Play or the phone maker supports one failing app: if other apps work, contact the app's developer.
Believing a Play Protect warning can be dismissed by turning scanning off: Google says to keep Play Protect on and uninstall the flagged app.