Great news everyone, you will be able to use the Instagram iPhone app, or any iPhone app for that matter, on iPadOS 15 in landscape mode.
iPadOS 15 Lets You Use iPhone-Only Apps in Landscape Mode
There are a ton of new features packed into iOS 15 and iPadOS 15, and right now we stumbled upon something which is going to make a lot of users happy. This feature allows you to use iPhone apps in landscape mode. Right now, if you have iPadOS 14 or earlier installed, you have to use apps in portrait mode, with the iPad itself held up straight.
So far, using iPhone-only apps on iPad has been an awful experience. If you frequently use your iPad with a keyboard or a keyboard case then tilting your head sideways or detaching your iPad is the way to go in order to deal with these apps. Not anymore with iPadOS 15.
Keep one thing in mind, the iPhone app itself will be in portrait mode even if your iPad is in landscape, as you can see from the photo above. This is one of those compromises which I will happily accept.
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