后退按钮是任何智能手机的基本功能。无论是Android中的专用后退按钮还是 iOS 中的上下文相关后退按钮，当它们停止工作时，您可能会发现自己被困住了，无法回到原来的位置。
修复 Android 中的后退按钮
Android手机最初在手机正面有硬件按钮，包括一个专用的后退按钮。现代安卓(Modern Android)手机现在倾向于全屏，所以这些按钮通常作为虚拟软件存在，位于屏幕的底部边缘(bottom edge)。对于某些全屏应用程序，例如游戏或流媒体视频，虚拟按钮可能会消失，但可以通过滑动显示。
一般来说，这是比旧的物理按钮更好的解决方案。但不幸的是，这确实意味着有时软件故障(software glitch)会让您失去这些关键控制。如果发生这种情况，您可以尝试以下技巧。
重启设备
即使是带有硬件后退按钮的(button didn)Android手机也不总是能承受最严重的软件错误。好消息是，大多数软件错误都可以通过重新启动手机来解决，所以先这样做吧。
检查系统更新
如果重新启动手机(phone doesn)不起作用，请检查是否有任何待处理的更新。如果错误导致您的后退按钮出现问题，则更新可能已修复它。
擦除系统缓存分区
系统缓存分区(system cache partition)是您的 Android 存储的一部分，系统存储(Android)更新(s storage)文件和其他内务缓存数据。大多数现代Android手机甚至不再有这个分区，而且它通常不是此类问题的罪魁祸首。但是，在某些情况下，缓存分区(cache partition)中的损坏可能会导致奇怪的系统行为。
擦除缓存分区(cache partition isn)并不难，也不会伤害任何东西，所以如果你别无选择，值得一试。不可能给出确切的说明，因为每部Android 手机(Android phone)都有不同的步骤，具体取决于Android的品牌和版本(brand and version)。您必须查看每个步骤如何适用于您的手机，但一般步骤如下：
- 关闭手机。
- 启动进入恢复模式(recovery mode)。
- 寻找“擦除缓存(wipe cache)”选项或类似的东西。
小心不要意外将手机恢复出厂设置！有关更多详细信息，请查看如何(How)在Android上启动并使用恢复模式(Boot Into & Use Recovery Mode)。
使用第三方返回按钮应用
这与其说是一种创可贴的修复，但如果似乎没有任何东西可以让您的后退按钮再次工作，您可以考虑使用第三方应用程序来模拟后退按钮。如果您的手机带有停止工作的物理后退按钮，这是继续使用设备的绝佳方式，直到您可以修复或更换它。
其中一些简单的应用程序在Play Store中，但有些值得一提。
Back Button（No Root）似乎是最受欢迎的按钮，顾名思义，您无需“root”手机即可使用该应用程序。即使您有一个工作后退按钮，此应用程序提供的多功能性也可能会有所帮助。
Back Button Anywhere是另一个流行的选项。它创建了一个浮动后退按钮，您可以将其移动到您喜欢的任何地方。该应用程序还提供了几个选项来自定义其外观，并为按钮提供自定义手势设置。可悲的是，这个应用程序是广告支持的，所以首先尝试返回按钮(Back Button)（无根(No Root)）。
恢复出厂设置您的手机
我们知道我们刚刚说过您应该小心不要将您的Android 手机(Android phone)恢复出厂设置。然而，如果一切都失败了，它可能是你唯一的选择。
与恢复模式(recovery mode)一样，每个品牌和版本(brand and version)的Android 手机(Android phone)都有其访问出厂重置选项(factory reset option)的方法。除非您的手机无法启动，否则您不必从恢复模式执行此操作。(recovery mode)您可以在设置中执行此操作，但具体位置不同。
在现代Android手机上，您可以使用全局搜索功能(search function)简单地搜索“恢复出厂设置(factory reset)” 。在我们的Samsung Galaxy S21 Ultra上，我们在Settings > General Management > Reset下找到了设置，但您的结果可能会有所不同。
查看如何硬重置冻结的 iPhone 或 Android 设备(How To Hard Reset a Frozen iPhone or Android Device)以获得更多帮助。
修复 iOS 应用程序中的后退按钮
iOS 与Android(Android)有不同的方法，缺少全局后退按钮。但是，iOS 中的应用程序会在屏幕左上方显示一个小快捷方式，标有您使用的最后一个应用程序或功能(app or function)。这使您可以返回到之前使用的应用程序。
iOS 中还有另一种类型的后退按钮，但这是基于每个应用程序实现的。例如，消息(Messages)返回按钮用于返回应用程序本身。它位于全局后退按钮的正下方，用于转到您刚刚使用的另一个应用程序中的上一个位置。
消息返回按钮错误
Apple Messages应用程序中似乎存在一个错误，有时会导致应用程序中的后退按钮消失。目前尚不完全清楚为什么会发生此错误，但只有三个可靠的解决方案：
- 杀死应用程序并重新启动它。
- 重新启动手机或平板电脑。
- 检查 iOS 更新。
另一个很棒的提示是，您不需要Messages中的后退按钮即可返回；您可以在屏幕中间从左向右滑动，从显示屏边缘开始。这与消息(Messages)返回按钮的作用相同，并且是一种更方便（如果宣传不佳）的应用程序功能。
检查辅助功能设置
iOS 包含许多辅助功能，可帮助有各种困难的用户使用手机，但其中一些功能可能会掩盖后退按钮！
您可以在Settings > Accessibility下找到这些选项。第一个感兴趣的是Zoom，另一个是Display & Text Size。
缩放(Zoom)会放大屏幕上的元素以使其更易于查看，但如果您放大，后退按钮将不在屏幕上。您可以在Settings > Accessibility > ZoomZoom是否打开，但如果您不小心将其激活，只需用三指双击(double-tap with three fingers)即可再次将其关闭。
另一个可能使后退按钮消失(button disappear)的设置是文本大小。转到Settings > Accessibility > Display & Text Size ，然后确保较大的文本(Larger Text )和螺栓文本(Bolt Text )都已关闭。
我会回来的
希望这些提示已在您的回程机票(return ticket)上盖章，您现在可以像往常一样“恢复”使用手机了。
How To Fix Back Button Not Working on iPhone and Android
The back button is an essential feature of any smartphone. Whethеr it’s the dedicаted bаck button in Androіd оr the contеxt-sensitive back button in iOS, when they stop working, уou might find yourself trapped with no way bаck to where you came from.
Fixing the Back Button in Android
Android phones originally had hardware buttons on the front of the phone, including a dedicated back button. Modern Android phones tend to be all screen now, so those buttons commonly exist as virtual software, sitting on the screen’s bottom edge. With some full-screen apps such as games or streaming videos, the virtual buttons may disappear but can be displayed with a swipe.
In general, this is a better solution than the old physical buttons. But unfortunately, it does mean that sometimes a software glitch leaves you without those crucial controls. If that happens, here are a few tricks you can try.
Restart the Device
Even Android phones with a hardware back button didn’t always withstand the worst software bugs. The good news is that most software bugs are resolved by restarting your phone, so start by doing that.
Check for a System Update
If rebooting your phone doesn’t work, check if there are any pending updates. If a bug is causing your back button problems, the update could have fixed it.
Wiping the System Cache Partition
The system cache partition is a part of your Android’s storage where the system stores update files and other housekeeping cache data. Most modern Android phones don’t even have this partition anymore, and it isn’t usually the culprit with problems like this. However, in some cases, corruption in the cache partition can cause odd system behaviors.
Wiping the cache partition isn’t hard and won’t hurt anything, so if you’re out of options, it’s worth a shot. It’s impossible to give exact instructions because every Android phone has different steps depending on the brand and version of Android. You’ll have to look up how each step works for your handset, but the general steps are as follows:
- Power off the handset.
- Boot into recovery mode.
- Look for a “wipe cache” option or something similar.
Be very careful not to accidentally factory reset your phone! For more detailed information, check out How To Boot Into & Use Recovery Mode On Android.
Use a Third-party Back Button App
This isn’t so much a fix as a band-aid, but if nothing seems to get your back button working again, you could consider using a third-party application to emulate the back button. If you have a phone with a physical back button that’s stopped working, this is an excellent way to keep using your device until you can get it fixed or replaced.
A few of these simple apps are in the Play Store, but some are worth mentioning by name.
Back Button (No Root) seems to be the most popular one, and as the name suggests, you don’t need to “root” your phone for the app to work. Even if you have a working back button, the versatility offered by this app could be helpful regardless.
Back Button Anywhere is another popular option. It creates a floating back button that you can move anywhere you like. The app also offers several options to customize its look and offers custom gesture settings for the button. Sadly, this app is ad-supported, so try Back Button (No Root) first.
Factory Reset Your Phone
We know we just said you should be careful not to factory reset your Android phone. Yet, if all else fails, it might be your only option.
As with recovery mode, every brand and version of Android phone has its method to access the factory reset option. You don’t have to do it from recovery mode unless your phone won’t boot. You can do it from within settings, but the exact location differs.
On modern Android phones, you can simply search for “factory reset” using the global search function. On our Samsung Galaxy S21 Ultra, we found the setting under Settings > General Management > Reset, but your results will likely vary.
Check out How To Hard Reset a Frozen iPhone or Android Device for more help.
Fixing the Back Button in iOS Apps
iOS has a different approach to Android, lacking a global back button. However, apps within iOS display a small shortcut at the top left of the screen labeled with the last app or function you were using. This lets you get back to the previous app you were using.
There’s another type of back button in iOS, but this is implemented on a per-app basis. For example, the Messages back button is used to go back within the app itself. It’s located just below the global back button, which is used to go to the previous location in another app you were just using.
The Messages Back Button Bug
There seems to be a bug in the Apple Messages app that sometimes makes the back button within the app disappear. It’s not entirely clear why this bug happens, but there are only three reliable solutions:
- Kill the app and restart it.
- Restart the phone or tablet.
- Check for iOS updates.
Another great tip is that you don’t need the back button in Messages to go back; you can swipe from left to right across the middle of the screen, starting at the edge of the display. This does the same job as the Messages back button and is a more convenient (if poorly advertised) app feature.
Check Accessibility Settings
iOS is packed with accessibility features to help users with various difficulties use their phone, but some of those features can obscure the back button!
You’ll find these options under Settings > Accessibility. The first one that’s of interest is Zoom, and the other is Display & Text Size.
Zoom enlarges the elements on the screen to make them easier to see, but if you’re zoomed in, the back button will be off-screen. You can check if Zoom is on under Settings > Accessibility > Zoom, but if you accidentally activate it, simply double-tap with three fingers to turn it off again.
The other setting that could make the back button disappear is text size. Go to Settings > Accessibility > Display & Text Size and then make sure that Larger Text and Bolt Text are both turned off.
I’ll Be Back
Hopefully, these tips have stamped your return ticket, and you’re now “back” to using your phone like you always have.
