While I can provide information on how to approach such a download, I must emphasize the importance of caution. Using official channels like the App Store is always the safest and most supported method for downloading and updating apps on iOS devices. If you're experiencing issues with downloading or updating Instagram through the App Store, reaching out to Apple's Support might provide a resolution.
If you’ve stumbled across the search term you’re likely looking for a way to install an older or modified version of Instagram on an iPhone, iPad, or iPod Touch. Maybe you want extra features, or perhaps you’re using an older device that can’t run the latest iOS.