iPhone 15 Pro overheating really quickly when using Lightroom app

I'm wondering if anyone else has had this issue. When I use the Lightroom app on my iPhone 15 Pro (newly purchased in Feb), it overheats quite significantly within literally a couple of minutes. This also then makes the screen dim as a result of the overheating, and the app starts performing quite slowly.

Has anyone else found this happening? I previously used the Android version of Lightroom on a Pixel and never had any such issues, so it came as a surprise.

Any tips would be greatly appreciated!