His other company (Square) has also started hiring some open source engineers in preparation for the time cryptocurrency eventually becomes internet's native currency.
In the long term it will help us be more and more like an internet company where we can launch a product ... and the whole world can use it, instead of having to go from market to market, to bank to bank to bank and from regulatory body to regulatory body.
While there's no mention that Square will have it's own coin, I think they're trying to compete with social media giants Facebook and Telegram. Like the two, Jack (being the founder of twitter and co-founder of Square) will also try to cash in on his social network's huge user base.