Not gonna lie OP, this thread made me laugh quite a bit. If only because I have a friend who also uses pretty much the same type of pinup anime girls as you do (large breasts/hips, skippy clothes and everything). And he uses them for more than his phone and PC, they can also be found on his Xbox 360 dash board as well. They make me extremely uncomfortable whenever I use his devices, so much so that I always use my things when I can. I called him out on it once, only because he bafflingly stated how 'tasteful' he felt his pinups were...and he was kinda embarrassed when I did. Which only made me wonder why he decided those pictures were a good idea in the first place, especially since we was so sensitive to what others felt about him back in those days.
So, yeah, I'm afraid that I agree with the majority here and say that image is pretty inappropriate. I don't like judging people before I fully meet them, but I can't help but make less than positive judgements of you (and my friend) when I see pictures like that. I rather not know what someone flaps off to by looking at their phone, sorry.
As for me, I usually just have pictures I've taken on my phone, mostly nature pictures, for my tablet and phone background. For my desktop background I usually have official wallpapers or concept art of a game I'm finishing or getting close to finish. Currently it is something from Child of Light. In the past I've had Azura's Wraith, Puppeteer, and Broken Age.