Coinbase is a leading digital currency platform and wallet where sellers and buyers can transact with new types of digital currencies such as Bitcoin, Ethereum, Litecoin, and Bitcoin Cash. The exchange was founded by Brian Armstrong and Fred Ehrsam in 2012 and is based in San Francisco, California. They focus on the US market, however, the company currently operates in 31 countries and offers storage of bitcoins in 190 countries around the world.
BITBOX is a Singapore-based cryptocurrency exchange launched in 2018. The team behind this platform is better known for a different project — messaging app LINE. The exchange is not available for the American citizens and doesn't support fiat money yet, but allegedly these problems are going to be addressed in the future. The trading volume is relatively low on BITBOX. By all valuations, this exchange ranks below the 100th position.
P2B is a centralized cryptocurrency platform, that offers more than 200 tokens. It covers the following markets: BTC, ETH, USD, EUR, and a number of stablecoins.