The nature of currency on my own perspectives, it has its specific character pertaining to digital currency because it's volatile and not regulated by government.
Unlike with fiat currency, authority and economic impact of a country depends on how the inflation works for them.
Cryptocurrency can be used in different ways, it can spend on goods and online payment and other spending needs. Also the most common experience that people usually do for it right now is online trading, it can be stocks or cryptocurrency.
Can be used as an assets is not the basic nature of the currency and not needed as well but cryptos giving us that opportunity so we can use them for it. The main two nature is it should have a stable value and accepted in the region while bitcoin mastered the acceptance since its accepted worldwide while the consistency in the price has put some barrier towards it.
Bitcoin can be used as Fiat in my county. But unfortunately it's not possible to many countries. In additional here, I am using bitcoin and crypto as assets also. Most of my saving are in crypto currency. I know crypto currency will send it back with 10 times profit. Only think need to done is, just hold till good price.