Back at the start of 2020, Instagram's official application for Windows 10, not much more than a web wrapper, appeared in the Store and was tagged as Windows 10 Mobile compatible. In fact, it wasn't really and, as we reported at the time, only worked in landscape mode and felt clunky as a result. This version has recently been withdrawn altogether and the official Instagram Windows 10 app is now only tagged for PC, i.e. Desktop, so doesn't appear in Store searches. However, don't lose heart, since it's really no great loss...

You see, Instagram's entire site is a PWA (Progressive Web Application) and this means that it (largely) works very well still with the Edge browser under Windows 10 Mobile, just bookmark instagram.com etc:

Which is pretty cool, though there are a few glitches here and there. The 'Activity' tab (the heart) doesn't work at the moment, for example. But being a PWA there's every chance things may get fixed here server-side.

If you did have the original Instagram official app installed then this will carry on working after a fashion, but the enforced landscape interface is a right pain and there are constant 'not supported' banners:

So best uninstall this and stick with the latest PWA in Edge.

Or go third party, with Winsta UWP continuing to get regular updates. This is what I use - and the 'activity' pane works fine in this. Along with notifications of Instagram DMs!