It isn't clear to me if the apps are being shut down: it says the website and online service. That could mean that the stand-alone and mobile apps can continue to generate revenue. But the 'Pro downloadable to use indefinitely' suggests that these apps will also be removed from respective stores.
afaik color.io has no apps on any appstore, just a web app which is basically an installable website.
The color.io website lists iOS, iPadOS, and Android alongside Windows and Mac. I don't know what to make of that, but it's curious.
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