Thank you for the details of the issue your partner is experiencing on his iPad. In my experience, when you are seeing an blue box, it indicates that you may have an accessibility feature turned on.
First, check the VoiceOver setting. I recommend trying the following:
Press the home button three times quickly. This is also called "Triple-click Home".
If the VoiceOver feature still is on, you can navigate to Settings > General > Accessibility and turn VoiceOver off here.
If it is too difficult to access those settings on the iPad, you can turn VoiceOver off using iTunes:
Managing accessibility features using iTunes
- Connect your iPhone, iPad, or iPod touch to any computer with iTunes installed.
- In iTunes, select your device.
- From the Summary pane, click Configure Universal Access in the Options section at the bottom.
- Select the feature you would like to use and click OK.
You can find the full article here:
Alternatively, you may have Switch Control turned on. You can disable this by going to Settings > General > Accessibility > Switch Control.
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