Originally Posted by
BobbySteel
I've found it to be maybe 5-10% better in my house
I've now fixed the cases for an iPhone 6, 8 and 11 Pro to be part of the same branded series with a hard plastic case layer first with a rubber-type case on top of the hard plastic case; and of those I'm finding the 11 Pro to have the weaker signal wi-fi router receptions at various places.
I'll try to do the same thing later with the same devices without any case and see what happens to the differences then.