In my opinion, you should do your own research.
Dont pick any crypto just because other people say it is going to RISE TO THE MOON in 2018, or because you saw a 30% increase in 1 day.
I cannot stress this enough, dont do what other people are doing but think for yourself.
Dont be one of those FOMO people.
Be critical and look at each coin from different perspectives.
Give a man a fish, and you feed him for a day. Teach a man to fish, and you feed him for a lifetime.
I think it is ethereum which is known to be next to Bitcoin when it comes on market popularity, demand and for having a large community of users. These factors made Ethereum a huge cryptocurrency throughout the years of its existence in the market contributing on its continuous market price growth as we can see based on the difference on its price from two years ago and up to the present.