I was surprised, too, to learn the S10 doesn't have a completely flat screen.
I bought my phone at Best Buy in Arden, North Carolina, where Louise is a very helpful and knowledgeable salesperson. I bought my screen protector there and had them apply it. Louise took two tries and another salesperson finally put on the protector perfectly, HOWEVER, it doesn't really go to the edges (which will probably help to keep it from peeling off) and there is no hole for the front camera, which I just about never use. I think I have guaranteed free replacement. I always like to have a "pro" install screen protectors because if they break the glass I don't have to pay for a replacement!
Oh...it was outrageously expensive, but worth the lack of aggravation of trying to put it on myself. You can see how much smaller than the screen it is in this picture.
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