Guys! Relax! Like many people already have mentioned, this might just be robots crawling your site for indexing purposes.
Russia has a lot of servers that's indexing different sites. You're all getting your panties in a bunch just for the fact that it comes from Russia. You do know that all Russians aren't black hat hackers? And that it's not targeting U.S. in particular? I'm Swedish and do see these referrals as well.
And when it comes to the referrals from Google Play and such, it's called "Referral spam". They manipulate the referral header on the request to look like it's coming from a specific URL so you will go in there and check. Just disregard it. It's harmless!
If you don't want this traffic to mess up your GA stats, just black list these Referrals/sources in GA. Blocking IP's will probably not work since this kind of traffic usually comes from a multitude of IP's.
Here's some more info about bots and referral spam: https://www.optimizesmart.com/geek-guide-removing-referrer-spam-google-analytics/
Please read the above link before you post any more "Oh.. help! Me too"-posts.