How to fix an iPhone 7 that keeps lagging, sluggish, and performing very slow after installing iOS update? [Troubleshooting Guide]

While software updates are generally aimed at serving good purpose to mobile devices, sometimes they can ruin things and cause chaos instead. Post-update issues are visible proofs on this notion. This is the main reason as to why it is highly recommended to backup your device before installing software update. While many people are able to benefit from software updates, others aren’t just that lucky as they end up facing new issues on their respective devices. Just like what has occurred to some owners of the iPhone 7, complaining about a laggy or sluggish iPhone after the iOS 11 update implementation. Why does this happen and what should be done in order to rectify the issue and get the iPhone back up and running smoothly again on the new iOS platform? You’re probably reading this content because you too are dealing with the same dilemma after attempting to take advantage of all the promising new features and enhancements brought by the latest version of iOS on your iPhone 7. If so, then this content is for you too. Read on to find out why your iPhone suddenly gets laggy, sluggish or performing very slowly after installing the latest iOS update.

Before going any further though, if you have other concerns with your new iPhone, make sure you drop by our iPhone 7 troubleshooting page for we have already started supporting the device. Moreover, if you need further assistance, you can always contact us by completing our iPhone issues questionnaire and providing us with sufficient information about the problem.

Why does your iPhone 7 become sluggish or perform very slow after installing software update?

When a device shows unusual performance after an update installation, it does not always mean that the update is at fault. In some cases, the problem is triggered by an existing application, which is not compatible with the new software installed on the device. For example, an iPhone 7 app is likely running on a version that does not meet the minimum system requirement of the new iOS 11 platform thus there’s a conflict. And that system conflict gives your iPhone a hard time getting that app work in the new platform thus causing its overall performance to slow down. It’s also possible that the app itself gets rogue and is no longer able to function as intended because its usual process is no longer supported by the new iPhone platform.

Another factor to consider in this case is the iPhone’s memory, which is most likely running out after the update implementation. Note that major software updates generally come in huge file size given its complex functions and the tons of new features and services packed with it. Assuming that the available storage space on the iPhone is already too low prior to the update installation, it can possibly become full after updating. As a result, memory issues begin to transpire including lags, sluggish or slow performance on the iPhone. So in this case, it’s the iPhone’s memory is to blame.

Cases of hardware damage caused by a software update are rare to none. Although there are some iPhone users who had claimed that an update had caused their device to brick and becomes totally useless. Those cases are just isolated though.

Potential solutions and workarounds to speed up your iPhone 7

The following solutions contains workarounds and generic procedures that will help speed up your device. You can try them first and then see if doing so can help your device back to its top speed performance.

First workaround: Free up some space on your iPhone 7

Memory issues like insufficient storage on the iPhone can trigger the same problem to occur on a device. To make sure this is not causing you this trouble, try to remove all unwanted files or contents that are no longer used like old messages, photos and videos from your iPhone. You can also set your Messages apps to automatically delete previous messages and conversations when it reached a specific period of time.

Another thing you can do to free up some space of your phone’s internal storage is to quit all running apps. Running of multiple apps in the background can slow down your device as each of these apps takes up memory space for each process requests. So the more apps running in the background, the more storage space they take up thus slowing down your device performance. Even if you’re no longer the apps, they remain running in the background and stays loaded into your iPhone’s memory until you close them. To eliminate this from the possible cause, launch the Multitasking view by double-tapping the Home button. This will open the screen that contains the preview of suspended apps. To close an app, swipe the app preview off the top of the screen. You can also configure your device to allow which apps are allowed to continue running even when they are not in used.  

  • To do so, select the apps to enable background app refresh on. You can work on this options by going to your iPhone Settings-> General-> Background App Refresh.

In this menu, you will see a list of apps that are currently allowed to keep running even when they’re not open. If you don’t think it’s necessary for apps to remain open then you can just turn off Background App Refresh instead.

Second workaround: Reset all settings on your iPhone 7.

A reset on the iPhone settings might also be needed especially if the problem is triggered by some messed up options from the update.

Some software updates, especially major versions automatically overrides your iPhone settings thus if you happened to customize certain options before the update, that can cause some conflicts. Tracking down what has changed or which options were overridden by the update can be very difficult so to save time and effort in spotting the error, you can just reset the entire settings on your device. However there are some downsides from doing so and that includes losing all your customized options at all. On the positive note, doing so can help rectify the glitch and correct whatever went wrong. Your iPhone will be restored to its default configurations. If possible, you can backup your important contents to iTunes for safekeeping before you proceed.

Reset all settings through your iPhone 7 Settings menu:

Once everything is set, go to your iPhone Settings-> General-> Reset All Settings then follow the onscreen prompts to complete the settings reset on your device.

Use iTunes to restore your iPhone 7 to factory defaults:

Alternatively you can use iTunes to reset your iPhone. To do so, have a computer ready and then follow these steps:


  • Connect your iPhone 7 to the computer. You can use either a Windows PC or Mac computer with the latest version of OS and iTunes program installed.
  • Open iTunes on the computer.
  • Select your iPhone 7 from the list of devices in iTunes.
  • Backup contents if necessary then click the option to Restore your iPhone to factory defaults.


Follow the onscreen prompts to complete the iPhone restore in iTunes and after that you should have your iPhone running fresh and free from errors.

Last resort: Perform a DFU Mode restore on your iPhone 7.

DFU stands for Device Firmware Update, a deepest type of restore applicable to your iPhone.

You can put your iPhone into DFU mode to downgrade the version of the iOS running on your device. This can be considered a better option given that the new iOS 11 version has caused your device or apps not to work properly. While this is actually discouraged, it’s an option to consider depending on the situation.


A DFU Mode restore should only be considered the very last resort as it is potentially risky too. You may have a higher chance to get the system issue resolved by this method but doing it wrong can also cause you to end up having a useless iPhone. In addition, downgrading your device can also violate its warranty. If you have nothing to lose and willing to do it at your own risk, then here’s how to enter DFU Mode on your iPhone 7 and restore the iPhone system:

  1. Start by connecting your iPhone to your computer using a USB cable or Lightning cable.
  2. Open iTunes on the computer.
  3. Turn off your iPhone by holding down the Power button and then slide to power off completely.
  4. With the device off, hold down the Power and Volume Down buttons for about 10 seconds.
  5. When the screen turns black, let go of Power button but keep holding down the Volume Down button for another 5 seconds. If you see the Apple logo, you might have held the button for too long. In this case, you’ll need to start all over. You’re not in DFU Mode if you see any icons or text on the device’s screen so you have to start again.
  6. If your iPhone screen turns black, it means you have successfully entered DFU Mode. You’re all set to proceed restoring your iPhone iOS when iTunes recognizes your iPhone and says it is connected.

Once you’re restoring your iPhone system in DFU Mode, you can exit this mode and go back to normal mode by restarting your device.

Seek More Help

If the prior methods have failed to fix the problem on your iPhone 7 performance and that your device still lags or loading very slow, then it’s time to give customer care a call for further assistance. You may also consider escalating the problem directly to Apple Support from them to tag it among other post-update issues to be addressed in the following iOS update in a form of fix patch.

Connect with us

If you need more help with the use of certain functions and features of the new Apple iPhone 7 smartphone, feel free to visit our Tutorial Page. There you can find a list of how-to contents, step-by-step tutorials, as well as answers to FAQs regarding iPhone 7. If you have other concerns or encountered some troubles while using the phone, you can reach us through this form. Just be sure to tell us more details of the problem or device issue(s) you may have and we will be more than happy to assist you further.

2 thoughts on “How to fix an iPhone 7 that keeps lagging, sluggish, and performing very slow after installing iOS update? [Troubleshooting Guide]”

  1. Why is my wife blaming our carrier for her iphone 7plus lack of performance. Very very slow. Im so sick of hearing it and she wont call them to help her. She’s driving me nuts! I have an android s6 plus and it works great. I can be on mine right beside her and mine is running gr8 and hers is very very slow. Neither one of us have memory problems because we dont download alot of stuff. Recently apple admitted slowing down their devices is thats whats going on? What is really happening? Apple is junk! Her phone as been doing this since day one. Someone help, she’s driving me insane!!

  2. Why is my pretend wife blaming our pretend carrier for her iphone 7plus lack of performance. Very very slow. Im so sick of people who don’t know the difference between I’m and Im. It’s driving me nuts! I have a pretend android s6 plus and I pretend it works great. I can pretend to be on mine right beside her and mine is running gr8 like frosted flakes and hers is very very slow. Neither one of us have memory problems because we dont know how to spell don’t and I download alot of stuff. Recently apple admitted slowing down their devices is thats whats going on with my pretend wife’s phone? What is really happening in my head? Apple is junk! Her pretend phone as been doing this since day one but Apple only slows down real phones with worn batteries. Is it different with pretend phones? Someone help, she’s driving me pretend insane!!

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