The below PNG image renders differently in Apple vs non-Apple decoders:

If you're using Apple-flavoured software, you should see "HELLO APPLE", and on all other software, you should see "HELLO WORLD".

Even on my apple watch

You can save it and test on your device

That's weird. To be honest I don't understand its principle ha ha

Original page:https://www.da.vidbuchanan.co.uk/widgets/pngdiff/

Principle:https://www.hackerfactor.com/blog/index.php?/archives/895-Connecting-the-iDOTs.html

LOL FROM AN APPLE USER!!!