The app icon is the button customers see on their phone home screen.
The splash screen logo is the logo customers see when they open your app.
An app icon is not a logo, Think of app icons as a small container of a fixed size which holds a “bite-sized” piece of visual information about the business. Yes, of course you could put your product or brand’s logo inside of an app icon if you want, but that doesn’t make your app icon a logo. Logos themselves are free to roam beyond the constraints of an app icon. They are scalable and can exist in any context: on flyers, websites, business cards, you name it
https://99designs.ca/blog/web-digital/how-to-design-app-icons
Has to be PNG format
1024 x 1024 dimension
No transparency mode (No Alpha channel)
Using Preview app (Mac):
Open the image
Command-Shift-S to Duplicate (creates a copy)
Command-S to Save
Deselect the "Alpha" checkbox
Delete " copy" from filename (including the space)
This will overwrite your original, if you want to keep the original, just leave "copy" in the name
Save
Click 'Replace' to confirm you want to overwrite the original
Only necessary if you are overwriting your original
Go to https://getorda.com.
Click Sign In in the top right and log in.
Go to Orda Dashboard -> App Storefront.
Upload the new app icon by clicking the app icon paperclip.
5. Upload the new logo by clicking the paperclip next to "Pick your logo."
6. Click Save in the top right.
An Apple and Google update is required to change your app icon or splash screen icon.