For me, bitcoin is a little bit of both. It is still a currency because of the fact that we can use it in any transaction that caters bitcoin. It becomes an asset because it's volatility range allows it to be profitable with the right strategy
Bitcoin can be now treated as asset because it depreciates and the value of it is still unstable to become a currency. It can be treated as half-asset and half-currency because bitcoin is a type of cryptocurrency. Bitcoin can be used in the future as an official digital currency once the value of it will become stable.
well, i also consider bitcoin as a very profitable asset. even it can be utilized in a short time. but, better to keep it longer. actually, bitcoin can be an asset or a currency that depends on its usefulness.