Next, tap the color picker and choose black, which is the most common color for obfuscation. Tap the highlighter again to set the thickness and opacity (make sure the slider is to the far right). Once you do, tap the highlighter tool, which looks like a thick marker. Take a screenshot and tap its thumbnail - or open an image or document in an app like Photos, Files, or Mail - then find the Markup tools. If you already have some obfuscated images, skip to the next section to see how to reveal what's hidden. To test it out, use the highlighter in Markup to obscure some text in a photo or screenshot. But for many colors, and most importantly, black and white, you can adjust the marker in editing to reveal the sensitive information it's hiding.Īffected iOS versions: iOS 15, iOS 14, iOS 13, iOS 12, iOS 11. If you move your finger back and forth a few times, it layers the effect, seemingly creating a non-transparent solid line that looks like it's hiding the stuff underneath it. Since it's a highlighter and not a solid marker, one swipe with your finger will create a transparent layer over the text, effectively highlighting it - even with the opacity at 100 percent.

Don't Miss: Blur Faces and Text in Videos with This Free, Easy-to-Use Video Editing App for iPhone.

The marker, aka highlighter, is a popular tool for quick obfuscation because of its thick strokes, but it has an opacity problem that's not visible to the naked eye. When using Markup in iOS, whether it's from Photos, Files, Mail, or another app, or right in the screenshot editor, you may only be partially hiding data you want to keep a secret.

But a digital marker may not hide everything. Whenever personal data is in them, such as debit card numbers, addresses, phone numbers, passwords, and other sensitive information, it's easy to jump into your iPhone's markup tools to black out the text before sharing. These days, most images we post online or share with others come from our smartphones.

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