Is it normal for an iPhone 11 to get warm during use?

Delete the App that makes the iPhone warm. and inform the App Developer.

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

"Is it normal for an iPhone 11 to get warm during use?: So guys I have a green iPhone 11 and sometimes when I go on some certain apps it gets warm. Should I be worried?"

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Normality for an iPhone to Get Hot During Use:

No. It is not normal. It is, however, an all-too commonly reported issue reported on these forums. Usually, it is reported to have occurred after installing an update, or due to having too little free space to operate the without getting hot. So, did you just update the iPhone? How much space remains? And what app are these that are giving you the issues.

Use my User Tip: Cooling Down an Overheating iPhone - User Tip

You need to have Apple perform diagnostics on your iPhone. It can be done in person at an Apple Retail Store or at an Apple Authorized Service Provider. You can also contact Apple Support and request remote diagnostics.

If you’re in the US please call  1-800-MY-APPLE or outside the US, consult the support articles below.

Contact Apple for support and service - Apple Support

Genius Bar Reservation and Apple Support Options - Apple

Explore Service Locations

Official Apple Support

kitan97 wrote:

I just realised my capacity is 76% but I don’t know how to replace an iPhone battery

Your iPhone’s battery has been significantly degraded and needs a replacement. That indeed can cause increased thermal temperatures. Make sure to get it replaced at your nearest Apple Store’s Genius Bar or Apple Authorized Service Provider only.

Genius Bar Reservation and Apple Support Options - Apple

No. Your iPhone when in use is designed to exert energy in the form of heat. If your iPhone really were “overheating” beyond that, it would display a “Temperature Warning” or “Charging on Hold” message, meaning that your iPhone is too hot to be used and is shutting off to cool down.

One thing to check though. Go to Settings > Battery > Battery Health and Charging. What is the percentage? If it’s below 80%, you need to have the battery replaced. You should have replaced it at least once by now. A significantly degraded battery requires longer to charge, more energy to use, and as a result can cause increased thermal temperatures.

One more thing as TheLittles stated, if you are almost out of storage, that can cause increased thermal temperatures. Make sure you have at least 10 GB of free system storage on your iPhone. The more is better. Your iPhone needs this extra space to perform tasks such as updating, indexing and more as storage is accumulative over time. You can check in Settings > General > iPhone Storage.