If you don't think this would be remarked about over the water in Europe (hello from the EU by the way), then you're not reading in the right places.
Sorry, but this kind of behaviour needs challenging. People will frequently not realise they're complicit. They aren't necessarily being malicious, but they are taking part. If it makes people uncomfortable that's tough, people are having some of their basic assumptions kicked out from under them, this is hard.
So am I now restricted not to use any woman in bikini? Or a woman wearing tan top? Are you saying by choosing a female in tan top is bad?
I don't see why we can't use those photos. I don't think people are sexualizing women. Sexualizing sounds like we are making a woman sexy. I am on Tumblr daily and I see a bunch of bloggers using sexy photos to attract followers so maybe we should stop doing that. I see instagram full of sexy photos and I guess we should stop doing that as well.
The iOS example seems off and I would agree with OP that that photo is questionable. the other two are fine. The second one doesn't really sexualize women. Just because the designer found a bunch of women avatars doesn't mean they are sexualizing women; maybe they haven't found a good looking guy avatar. Maybe those are friends of the designer.
The third app is also fine. To be fair, make a poll and ask how many women like seeing a beautiful woman picture than a man's picture.
