in my opinion the most developed coin later is vexanium
because I read the vexanium project to launch mainnet in Q1 2019
Their products are currently running smoothly
I am not pretty sure that this coin would be doing great for there are better coin than this in the market. Just take consideration on the coinmarketcap.com and see the marlet cap volume of every crypto. Relatively the best crypto rank in the first 10 so if I were to invest then I will on the first 4 crypto in the coinmarketcap.com list.