there are so many different cryptos (over 1000) but the only two I see that are accepted at online stores are Bitcoin, Ethereum, and sometimes Bitcoin cash.
Nano seems to have good technology with the low fees and fast transactions, but the price is too volatile to be used as a currency right now. Btc/ETh crashed a lot but Nano took a much larger dip, its down to $1 from a $20 high. People are scared to use nano because it crashed 95% in price.
I'm not really into Nano but this coin is really undervalued due to there are already coins placed on the top but overall I do see this coin is much worthy than on most coins listed on 3-26 place.(Currently Nano is on 27 rank).