Best cryptocurrency to invest in 2018:
Arionum
Triton
Clearcoin
I do not know how about these three coins, whether it is worth investing in them, but Ethereum is definitely worth buying. Although you can buy just a little, it will be even better than buying one.
and I myself prefer ethereum to be used as an investment this year or in the years to come, because I believe and strongly believe in ethereum will definitely give good prices later
Now, when the market has a great choice of altcoins, you can easily pick the best cryptocurrencies. I mean, you can buy Eidoo, Credits, TRON, Lisk, and OMG.