This app was mentioned in 4 comments, with an average of 2.50 upvotes
A recommendation for the boys if they want a good risk app to get some practice in on, Lux DLX is my go-to. It's a great time-waster, plus you can download lots of different maps, and there's pretty flexible rule adjustments. There's a free version too.
Also the graphics are nice and simple, unlike the game in the video which made me feel like I was supposed to be wearing 3D glasses the whole time.
PS I'm loving these board-game games, keep 'em coming!!
I've been playing Lux DLX for years https://play.google.com/store/apps/details?id=com.sillysoft.LuxDLX&hl=en
There are dozens of additional maps you can download for free as well.
Looks like it is getting bad reviews because it is crashing, which hasn't happened with me.
Linkme: Lux DLX