Girlfriend app... for Android phone, yes.
Girl-Friend-App, yes. If you browse Google play with language set in either Korean or Japanese, you can find a fair amount of Girlfriend app.
What the app does is that it gives you ... a digital, eventually nagging, girlfriend. It is fairly popular among young guys. Even some middle-age men have it on their phone.
The app works by gently forcing its players to pay attention to it. You have to periodically play the app in order to increase affinity to the digial girl. High affinity allows its players to change her costomes (which players need to purchase with real money). Reaching higher affinity requires gifts, some of which must be purchased with real money.
Just looking at the amount of reviews such app receives indicate that it has some dedicated playerbase.
The four reviews displayed on the image above say things like "I've finally got a girlfriend!", "It's good, heh. Item arts are lovely.", "How should I respond when my girlfriend gets ill TT", and "I've got a girlfriend in my palm."
I am not writing this to judge them although it's hard to resist hearing a snicker or two in my head as I write this. But each to their own. Let's just leave it at that.
These kind of apps work by gradually making its players addicted and eventually force them to spend real money for gifts and costumes. And as always, there are addicts who can't control themselves and end up spending quite large amount of money over their digital girlfriends.
These apps are known to consistantly nag you by making your phone vibrate periodically. Thankfully, these apps are designed to stay slient during night time.