If you play about on WeChat etc in China, most of the time, you aren't going to get to shag them; they're just narcissist sluts that long for the attention. Getting pics is all well and good, if if you're bored and haven't got much better to do; but if you're really desperate; just hang about around a mall in the daytime/at weekends and do things the old fashioned way, by approaching, talking to them etc.
Chinese girls don't tend to care about a foreigner's novelty value so much now, they know that most are teachers, don't earn as much as middle-class Chinese guys. If you speak Chinese, are a tad mysterious, you can still easily pick up girls, but the average laowai will just pick up the crumbs that Chinese guys don't want. Then again, half of them still think that a below average Chinese girl is some kind of exotic beauty that is hard to find, so everyone wins.