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???
For now I don't see a serious compatibility bitcoin which will have an ability to overcome it or replace it from the first place on the market, there are some good projects but not that level as Bitcoin. Maybe in the future will be developed something like that.