There are many cryptocurrencies out there, the fluctuation is wide and big. Theres a need of a coin that uses a process to stabilize its value.
No doubt that there is no other cryptocurrency or altcoin that can supersede the bitcoin. At least not for the next 5-10 years. Of course there are many rising competitors like Ethereum, ripple and litecoin.
Do you agree???
It's hard and it's very difficult to say if there are coins that will replace bitcoin, because even though there are a number of other potential coins like Ether, there are still many that need to be improved before going beyond the current level of bitcoin. Everything is still possible, but it may take tens or hundreds of years.