In the 21st century, flirting is no longer just something you do at a bar or club after a few drinks to build up your confidence. In fact, more often than not, it's a text- or photo-based exchange conducted between smartphones, with fingers doing the flirting that tongues used to manage. Getting exact data on how many people are digitizing their flirtations isn't easy, but for one example, consider the DirtySnapchat subreddit : it boasts over one million members and nearly 130,000 weekly visitors. Of course, as sexting became more popular, we gained exponentially more ways to engage in it, from naughty websites to flirty dating apps to clever in-between options, where a suggestive text message or a racy photo are all part of the fun.…