Expo build fail: Repeated error about transparency on icon in expo build despite no transparency

Question

I have been trying all afternoon to run expo build:ios with expo-cli for the first time so I can get my first expo app onto TestFlight but I'm repeatedly getting the error: "Your application icon can't have transparency if you wish to upload your app to Apple Store."

I have checked with get info and the icon file is showing no alpha channel. I've put the icon on a white background and merged the layers in photoshop which is supposed to remove transparency, I've even tried saving it as a jpeg so there isn't transparency but the result is the same. I've checked my app.json file and it's in line with the example given in a similar issue on the expo github channel. It's also here: https://github.com/callyb/expo-cli-build-error/blob/master/app.json.

I am at a loss - the app works great on both my devices and simulators, published on expo and running in expo production mode and I just can't see where the error might be (I'm assuming it's probably not the icon...) Does anyone have any suggestions? Are there any tools I can use to check where the error may be? Many thanks for any help...

Answer 1

I used this website:

https://www.online-image-editor.com/

Upload image -> Advanced settings -> Transparency -> Remove transparency -> Save

Answer 2

I was facing the same issue, i had png which was using aplha.

To resolve the issue, open your png image and save it without aplha setting.

Here is the github reference for checking alpha in PGN. don't allow to use png icon with alpha channel

If you are on a macbook, just preview your icon and export it by unchecking Alpha property.