apps on iPad glitching after 26.6 update

This is a known graphical UI layout glitch in the 26.6 update where the system-wide overlay sheets (the dialogue boxes responsible for saving, exporting, or picking files) instantly crash or dismiss themselves due to a conflict with rendering text or animations.

Since it affects both native apps like Safari and third-party tools, it is definitely a core system bug rather than individual app issues. Here are the most effective ways to force the system interface to stabilize:

• The Language Toggle Trick (Most Effective): Go to Settings > General > Language & Region. Add a secondary language (like English UK or Spanish), make it the primary language, and let the device soft-reboot the interface. Then, switch back to your original primary language. This forces the system layout engine to rebuild all localization and interface assets, which often stops the flickering dialogue bug.
• Turn Off Stage Manager: If you are using the multi-window layout feature, it can sometimes miscalculate the safe bounds for popup sheets. Swipe down from the top right to open the control panel and turn off the multi-window icon to see if the standard full-screen popups return to normal.
• Disable Hardware Keyboard Customizations: Go to Settings > General > Keyboard. If you have an external keyboard connected, disconnect it. Also, toggle off predictive text and auto-correction temporarily. A glitch in the system keyboard window layer can actively reject underlying app dialogue inputs.
• Reset All Settings: If the layout loop continues, navigate to Settings > General > Transfer or Reset iPad > Reset > Reset All Settings. This will clear systemic caches, interface preferences, and permission maps without erasing your files, photos, or documents.

While not suggesting that you don't have a problem in need of resolution, your described issue across multiple Apps does not appear to be widespread. If it were, this Support Community would be overflowing with similar reports.

Begin with updating your iPad to the most recent version of iPadOS. At the time of writing, iPadOS 26.6.1 is current.

If your iPad is not operating as expected, try a forced-restart - as this will often clear an isolated or post-update software issue:

Force restart iPad (models with Face ID or with Touch ID in the top button)

If your iPad doesn’t have the Home button, do the following:

1. Press and quickly release the volume button nearest to the top button.
2. Press and quickly release the volume button farthest from the top button.
3. Press and hold the top button.
4. When the Apple logo appears, release the top button.

If the problem persists after performing the forced-restart, it may be necessary to reset your iPad settings. While this reset will not cause any loss of data, as a precaution, it is always wise to ensure that you have a current iCloud or iTunes backup before performing the reset:

How to back up your iPhone, iPad, and iPod touch - Apple Support

When you are happy to proceed, you can perform the reset from iPad settings:

Settings > General > Transfer or Reset iPad > Reset > Reset All Settings

If the problem still doesn’t clear, the next step is to reset the iPad to factory settings:

Restore your iPhone, iPad, or iPod to factory settings - Apple Support

As a diagnostic exercise, do not restore your iCloud/iTunes backup to the iPad at this time. Instead, set-up "as new" with your Apple Account credentials - and install and test the Apps with which you experienced difficultly. This test is intended to verify normal operation of the iPad in its default state. Having verified normal operation, you can then reset the iPad and restore your backup that will include all your data and device settings.

Restore your iPhone, iPad, or iPod touch from a backup - Apple Support

In the unlikely event that the problem remains, this would suggest a system hardware issue that would benefit from further investigation by Apple Support. You can contact the Support Team using the Support link at top-right or bottom-left of this page - and request a remote diagnostic test of your iPad. Alternatively you can initiate and manage your support cases from Apple devices using the excellent Apple Support App. If not already installed the App can be downloaded from the App Store:

https://apps.apple.com/app/apple-support/id1130498044

You might also visit the Genius Bar at your local Apple Store or Apple Authorised Service Provider (AASP) - where the technicians will be able to test and assess your iPad - and you can explore your available options:

Genius Bar Reservation and Apple Support Options - Apple