How to use bold text in your text messages on an iPhone by enabling subject lines

You can use bold text on your iPhone in text messages by creating a subject line after enabling the feature in Settings. Here ...

iOS 15 lets you change your iPhone's font size for every app or individual ones — here's how

You can't change the actual font on your iPhone, but you can change the font size in a couple of different ways, especially if you have iOS 15.