How Logout By Uninstalling Instagram On Device
Users log out of Instagram, uninstall and reinstall the app. However, this is not an efficient way to opt out of Instagram. Instagram will save your login, but clearing the account before you uninstall will help clear the cache.
Below is the process with how to opt out of Instagram. In addition, the process works equally well for Android and iOS phones, so you can follow the same steps for both operating systems.