If you find yourself squinting at your iPhone when you're trying to read a message or an email, then you might be pleased to hear that there is an easy way to make text bigger on an iPhone.
To make text bigger, just go to Settings > General > Accessibility, and then tap on Large Text. Now, you'll see several different text sizes that you can choose from, ranging from 20pt all the way up to 56pt.
Now that you've chosen a size, your text will be bigger in Mail, Contacts, Calendars, Messages and Notes.
To make text bigger in Safari, you can pinch and zoom in to web pages.