Some iPhone apps give you the option to increase or decrease text size.

But for all intents and purposes, developers who have implemented the ability to change text size in an app have wasted their time because the feature remains limited to their specific app.

Wouldn’t it be great if the user could choose their preferred text size once and trust the operating system to automatically switch fonts in apps as needed?

That’s exactly what the Dynamic Type feature was designed for!

Provided an app uses adaptive layout, this super handy feature will automatically adjusts tracking and leading for every system font size and text style to match your size preference.

Dynamic Type will even attempt to adapt user interfaces at large font sizes in order to make tapping buttons or accessing important functions within apps easier.

Adjusting the size of text content is crucial for Apple customers who suffer from astigmatism or other vision problems. Increasing the system font size to suit your liking will help reduce eye strain so you won’t have to squint when reading your email, surfing the web and more.

Here’s how.

How to increase text size on iPhone and iPad

To change the system font size in Mail, Contacts, Calendar, Phone and Notes, as well as in any third-party apps that support the Dynamic Type feature, do the following:

1) Open the Settings app on your iOS device.

2) Choose Display & Brightness from the list.

3) Tap Text Size.

Drag the slider to the left to make the font size smaller or to the right to increase text size.

Drag the slider to the center to reset system fonts to their default size.

“Apps that support Dynamic Type will adjust to your preferred reading size below,” reads the feature’s description. I cranked the font size all the way up and screenshotted a few apps.

Left to right: large font size in Apple News, App Store and Apple Maps

Apple’s first-party apps are showcase examples of proper Dynamic Type support. In Apple News or App Store, for instance, making the text bigger increases the font size for body text while ensuring that things like the byline, category name or price are not comically large.

Left to right: large font size in Twitterrific, Twitter and Instagram

Third-party apps such as Twitter and Twitterrific support Dynamic Type in a way that won’t break the interface at large font sizes. Instagram could use more work in that department because upping the fonts makes everything indiscriminately bigger, which looks odd on bio pages.

Dynamic Type isn’t just for  native apps—even web developers can easily support this feature in HTML pages by using appropriate CSS font presets. Unless your favorite website supports Dynamic Type, it probably won’t automatically scale the text to match the selected font size.

To make the fonts even bigger than the slider allows, you’ll need to visit accessibility settings.

Making the font size even bigger

1) Open the Settings app on your iOS device.

2) Tap General.

3) Tap Accessibility.

4) Tap Larger Text.

5) Toggle the switch Larger Accessibility Sizes to reveal bigger font options.

6) Now drag the slider to select the font size you want.

iOS 11+ will attempt to adjust the user interface elements at large font sizes, but keep in mind that oversized fonts might make it difficult to tap buttons within apps.

iPhone and iPad have supported Dynamic Type since iOS 7.

Even if you have perfect 20/20 vision and have no use for Dynamic Type, chances are you’re an important tech support person to your friends and family. It is therefore a good idea to memorize this tip because your parents will likely prefer the bigger fonts.

Need help? Ask iDB!

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Got stuck? Not sure how to do certain things on your Apple device? Let us know via help@iDownloadBlog.com and a future tutorial might provide a solution.

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