I think this is a great project that will do well once it launches into the global market. there are 3m users already in just korea which has only a population of 50m so about 7% of the population.
there is 8 billion people in the world so we can expect this app to have almost 700m users
A funny comparison, this world has 8 billion people but not too many people know about cryptocurrency. And if you hope, this project has 700 million users, they will surely become the leading altcoin in this market, even it can beat bitcoin.
Yes I think it is completely possible, because while not too many people know about cryptocurrency almost everyone plays games on their phone. if they target gamers then they will be able to convert those users into cryptocurrency holders.