In the long term, there must be one or several of the best digital encryption currency is widely accepted by the market.
In my view the best shot at crypto dominance is a easy to use coin that is fast and secure. It will need to be a PoW/PoS hybrid with an Android app that can mint new coins and has large community devoted to it's development.
The only alt I know about that is anywhere near being that is MINT. And at under 20 satosh right now it's a hell of a bargain. There's no completed android app as of yet but there will be soon enough. It's being developed now.