You can easily change Gmail display by accessing Gmail's quick settings menu that pops up beside your inbox when you click ...
To change the default email app on an iPhone, you'll need to upgrade to iOS 14 and make sure you have a compatible app ...
If you own an iPhone and want to change the default apps, now you can do so. Gone are the times when you couldn't and were limited to the apps that Apple wanted you to use, especially the Safari ...