This Hidden iOS Feature Lets You Draw Perfect Shapes on Your Photos

Do you use Markup to edit your photos and screenshots on your iPhone? Then you need to know this secret trick.

Nelson Aguilar
Nelson Aguilar is an LA-based tech how-to writer and graduate of UCLA. With more than a decade of experience, he covers Apple and Google and writes on iPhone and Android features, privacy and security settings and more.
Nelson Aguilar
2 min read
iOS 16
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I have way too many photos and screenshots saved on my iPhone -- nearly 60,000 images are sitting in my camera roll as I write this.

And I like to draw on many of them, especially screenshots of funny tweets, important text messages or interesting excerpts from an online article, to highlight certain parts before I share them to friends and family.

Unfortunately, it's tough to draw well with your finger on a rather small phone screen, and so my lines, circles and squares are usually all pretty shoddy -- but hey, what can you do?

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Well, it turns out there is something you can do, because there's a hidden iOS feature built into the Markup photo editor that allows you to transform your bad drawings into perfect shapes. 

And it's been around since at least iOS 15.

If you want to check out more hidden features on your iPhone, here's how to unlock your iPhone's secret trackpad and seven hidden features on iOS 16 we were surprised to find, like Nintendo Switch Joy-Con support.

How to turn your finger scribbles into perfect shapes on iOS 16

To access this hidden editing feature, you can either take a screenshot or go into an existing one in your camera roll. 

If you take a screenshot, tap the tiny preview in the bottom-left. This is the easiest way to draw on your screenshot. You can also go into the Photos app, tap the screenshot you want to draw on, hit Edit on the top-right and then tap the Markup icon (pen in a circle). And obviously, you can do this with regular photos as well.

Next, choose a drawing option from the bottom of the screen: pen, highlighter or pencil.

And finally, draw what you want, whether it's a line, arrow or circle. However, don't lift your finger after you finish drawing -- instead, hold your finger down for a few seconds, and whatever shape it is that you drew will be replaced with a perfect version of it.

Screenshot editing tool on iOS 16

Here you can see a bad drawing of a circle turned into a perfect circle.

Nelson Aguilar/CNET

For example, if you draw a poor circle and hold your finger down when you're finished, your bad circle will be replaced with a perfectly drawn circle. If you draw a crooked line, it'll be replaced with a perfectly straight line. This feature works with several shapes, including:

  • Circles
  • Lines
  • Quadrilaterals (squares, rectangles, etc.)
  • Pentagons
  • Hexagons
  • Arrows
  • Stars
  • Clouds

Once you're finished crafting your perfect shapes, hit Done to save them onto your screenshot. And that's it!

For more, here's here's when we'll get the iPhone battery icon we really want and how to make the iPhone 14Pro's always-on-display better.