I noticed some of my iPhone photos look overly bright due to HDR processing. How can HDR be removed or adjusted from an iPhone photo after it’s taken using built-in settings or editing tools?

Oh, I've been there—photos that look almost radioactive because of HDR! The good news is you have a few solid options right on your phone. First, know that on newer iPhones (with iOS 16 and later), the default is Smart HDR, which blends multiple exposures automatically. You can't "remove" HDR after the fact because it's baked into the image data, but you can tone it down dramatically.

1. Use the Photos App Editor: Open the photo, tap "Edit," and then tap the magic wand icon for "Auto" adjustments. This often balances HDR well. If that's not enough, use the sliders manually. Pull down "Highlights" to recover blown-out bright areas. Sometimes increasing "Shadows" a tiny bit and slightly decreasing "Contrast" can make the HDR look more natural.
2. Turn HDR Off for Future Shots: Go to Settings > Camera. Turn off "Smart HDR". Now, when you take a photo, your iPhone will save both an HDR and a non-HDR version. The one you'll see in your Photos app is the non-HDR one. This is the best long-term fix if you consistently dislike the HDR look.

For the photo you already have, playing with Highlights and Shadows is your best bet. It's surprising how much you can salvage!