Good day. How can I downgrade my iOS 14 to iOS 12

The app is the iOS App Store.

The miminum iOS version goes all the way back to iOS 9!

If it worked with iOS 12, it should work with iPadOS.

Here's the iOS App Store link.

https://apps.apple.com/us/app/pocketwise-sfe/id1193943069

Why are you unable to downgrade? I’ll try to explain...

iOS/iPadOS are secure Operating Systems. All installable code is digitally “signed” by Apple. This code-signing ensures that only “secure” and supported computer software can be installed on your device.

Code-signing applies equally to Apps.

Apple will only digitally sign OS versions that are considered current and in-support. When older versions of the OS for a particular device model cease to be supported, the digital signature is revoked.

When system or App software is installed, the digital signature is verified as being valid; if the signature cannot be verified, it cannot be installed. It is for this reason that you cannot install an older version of iOS.

If you have an App that does not support a more recent version of iOS/iPadOS than it was designed to be compatible, this would suggest that the App Developer has abandoned the App - and is now obsolete.

Unless Apps are updated by Developers to be compatible with your installed version of iPadOS, you’ll not be able to use the Apps with your iPad.

Any App issues should be directed to the App Developer:

How to contact an app developer – Apple Support

as are the Apps for a particular model of device. Any

This has never been possible.

And you wouldn't want to downgrade to iOS 12 at this late stage.

Many apps will be moving on from iOS 12 within the next year or two.

What is wrong with your 5th gen iPad on iPadOS 14?

Maybe all of of us here can sort out your issues.

I have two much older 2015 iPad Pro models and iPadOS 14 has been working great on these devices.

What are your iPadOS 14 issues?

It is not possible to restore an earlier version of iOS/iPadOS.