I actually am not sure. I bought a used copy from this version on amazon
and I initially bought an orange flag and dice to match the pieces, only to find out the boardgame I got was a different copy entirely.
Give Grand Strategy a try. Free to play. No Ads. Just Risk.
There is a mobile client, but it works best on tablet.
https://play.google.com/store/apps/details?id=org.grandstrategy.client
According the Amazon reviews the rules make little sense, as you say. Very often in parody games the rules are not quite as rigorous as "straight" games, but in this case it looks like they completely phoned it in.
This is a link to an app you can download on your phone that's the easiest way to play https://play.google.com/store/apps/details?id=com.hasbro.riskbigscreen&hl=en_AU&referrer=utm_source%3Dgoogle%26utm_medium%3Dorganic%26utm_term%3Drisk+app
There are other websites online but I always found them confusing
It's pricey as all hell but I don't regret buying my 40th Anniversary edition. Metallic pieces, heavy die, beautiful map, it's a set I will keep for decades and eventually pass it down to a lucky youngster.
It's from Hasbro and is pretty good. One free game every eight hours, though...
Big Screen is the extended name of the app. Guess they picked it as a way to leverage that it can work in Google Cast?
Google Play link : https://play.google.com/store/apps/details?id=com.hasbro.riskbigscreen