"This application requires iOS 13.4 or later"

You cannot pick and choose an iOS version. What you get is Settings > General > Software update > [All options are available here]

If iOS updates are no longer being released for your device, it typically means that the device has reached its end of life in terms of software support from Apple. In such cases, there are a few options you can consider:

1. Although major iOS updates may no longer be available, Apple may continue to release security updates for older devices. Ensure that your device is running the latest available version of iOS for its generation to maintain the highest level of security.
2. As iOS versions advance, some newer apps may not be compatible with older iOS versions. You may need to rely on older versions of apps or find alternative apps that are compatible with your device's iOS version.
   1. Ask the App developer to release the app for lower iOS versions also. Netflix & Amazon has done it.
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3. If your device is no longer receiving software updates, it may be a good time to consider upgrading to a newer device that is supported by the latest iOS updates. Upgrading to a newer device will ensure that you continue to receive the latest features, security updates, and app compatibility. Selection of a mobile model/brand is driv… - Apple Community

Remember to regularly back up your data to avoid losing any important information during the transition to a new device.

It's worth noting that the availability of updates and options may vary depending on the specific device model and its hardware capabilities.

An iPhone 6 can't be updated beyond 12.5.6, it doesn't have the hardware needed to run anything higher.

If you need a higher iOS version, you will have to purchase a newer phone.

Use the web versions of Facebook & YouTube

This is not a chat service, and is not a way to communicate directly with Apple; it is a user-to-user technical support forum. If you have a question or issue that you think another user can help you with please describe it in as much detail as you can and a user who sees your request and thinks they can help will answer, but that might not be immediate; it could be hours later. Here is some advice on how to do that effectively→Writing an effective Apple Support Communities post.

If you want to contact Apple use the Support link at the very top of this page or call Apple by choosing a number from this list→Contact Apple for support and service - Apple Support

lobsterghost1 wrote:

True that an iPhone 7 is most certainly eligible to run the latest version of iOS 15. But they will most likely need to use their computer and update the iPhone using iTunes (Windows) or Finder (Mac) after skipping a few years worth of iOS updates.

The OP, whose tagline says "iPhone 7, iOS 13" (implying that they're running a version of iOS 13 earlier than 13.4), may well be in that boat. Here are some support articles that the OP may want to consult.

Update your iPhone or iPad - Apple Support

Update your iPhone, iPad, or iPod touch with the Finder - Apple Support

Update your iPhone, iPad, or iPod touch with iTunes - Apple Support

If your iPhone or iPad won't update - Apple Support

attila13 wrote:

ios 13.4

What's your question?

I do not believe that iOS 13.4 is still available. If you have an iPhone that can run a later version of iOS than that, you can update to a later version of Apple's choice by following Apple's directions.

Update your iPhone or iPad - Apple Support

If you have an iPhone 6 or 6 Plus, you cannot upgrade to iOS 13.4, and you cannot run apps that require iOS 13.4 or later. For the iPhone 6 and 6 Plus, the latest version of iOS 12 (currently 12.5.7) is the end of the line.

What phone do you have? If you're on a 3G cell network, than I'm guessing you have a very old phone.

An iPhone 5 can't be updated beyond 10.3.4.

An iPhone 5S, 6/6plus can't be updated beyond 12.5.6, it doesn't have the hardware needed to run anything higher.

If you need a higher iOS version, you will have to purchase a newer phone.

Borrow an iphone from your friend which is running on iOS 14 or later and sign in with your Apple ID, then download the app on your friends phone, If you see on your phone you should see a download option, Hope it helps.

https://www.youtube.com/watch?v=VV_8NQi1xRc if you prefer watching(not my channel)

I tried and it worked.

As the others have said, there is a workaround to this issue. The workaround is to download it on a newer device so it will be saved to the purchased section in your Apple ID, after which you can go ahead and install it on the iPhone with the older iOS version, such as iOS 12.5.7. It will allow you to install the latest compatible version instead.

sadilla wrote:

iOS 12.5.7 requires 13.4

You will need a newer phone that can be upgraded to iOS 15. (iOS 13 is no longer available). You need an iPhone 6S or later. You can still access Facebook using the Safari browser.

Mitchellegrace wrote:

why Facebook are not install

Facebook requires an iPhone which runs at least iOS 13.4. If you iPhone isn't capable of running iOS 13.4 or higher, then you can't install Facebook on your iPhone.

ejazullah wrote:

want to make my this application requires ios go away

Buy the company who makes the application and then you can tell them what versions of iOS you expect them to support. Buying a newer iPhone, which supports the iOS version you need to run the application seems a far less and complex thing to do.

mikel251 wrote:

it's hard to find the install of ios 13.4

"This application requires iOS 13.4 or later."

An iPhone 7 owner who is running iOS 10.0 – 12.* now, and went to upgrade, would be offered the latest release of iOS 15.

Servant of Cats wrote:

mikel251 wrote:

it's hard to find the install of ios 13.4

"This application requires iOS 13.4 or later."

An iPhone 7 owner who is running iOS 10.0 – 12.* now, and went to upgrade, would be offered the latest release of iOS 15.

True that an iPhone 7 is most certainly eligible to run the latest version of iOS 15. But they will most likely need to use their computer and update the iPhone using iTunes (Windows) or Finder (Mac) after skipping a few years worth of iOS updates.

Again true. But the post of yours I was responding to, suggested a person with an iPhone 7, which is running iOS 10 - 12 would be offered iOS 15, may not be true. Often, people who don't update their iPhone for a couple years, skipping lots of updates, need to update their iPhone using a computer.

RE: “pls give solution”

The solution is that if an app requires iOS 13.4 or later, and your phone can’t run a recent enough version of iOS to satisfy the app’s requirements, you don’t get to run that app on that phone.