How can I turn off strikethrough feature on my iPhone?

Wrapping text in three tildes—like ~~~this~~~ won’t apply strikethrough (or any formatting) in iPhone's native apps like Messages, Notes, or Mail.

• ~word~, ~~word~~, or ~~~word~~~ → All just show up as plain text.
• iOS isn't Markdown-savvy in most native apps.

Unlike apps that support Markdown (like Slack, Discord, or some blogging platforms), iOS doesn’t interpret triple tildes—or any number of tildes—as formatting commands.

The app developer may not have updated their software to ensure compatibility with the iOS version your device is currently running.

If you encounter any challenges with third-party applications, the best course of action is to directly contact the app developer for further assistance. Here's a brief guide on how to do it:

1. Identify the app developer.
2. Visit their website or app store listing.
3. Look for their contact information or support channels.
4. Clearly describe the issue you are facing.
5. Provide any necessary information they may need.
6. Follow their instructions and provide feedback.
7. Be patient and follow up if needed.

By reaching out to the app developer, you increase your chances of receiving accurate and personalized support for the challenges you're experiencing. To contact an App developer --> How to contact an app developer - Apple Support

Minminmini wrote:

as a korean, i have a txt habit

Does this happen in Apple's Messages app? Or are you talking about a 3rd party app. If only in the latter, you need to contact the people who make it.

Please review the Apple Support article I linked to below.

Save keystrokes with text replacements on iPhone - Apple Support

Are you using the default Apple Keyboard or a third party?