I guess that will be Iota, Ripple, Ethereum, maybe Monero and Incent.
And finally a new Coin will come, that will top Bitcoin. That Coin will be made by an absolutely genius Developer who will focus the property of very very simple and uncomplicated usability made for all the average people using it everyday in normal everyday-life. When your Grandmother uses this coin, then you know this is it.
Well my grandma uses http:// https:// and the DNS system all the time without even realising it.
Very soon she'll using bzz:// bzzr:// and ENS without even realising.