An interesting avenue to explore is the wavelet coherence between different cryptocurrencies, allowing any relationships between different cryptocurrencies to be detected and documented. Relationships between different cryptocurrencies would be of interest for those searching for diversification within cryptocurrency markets, especially to those managing a portfolio of cryptocurrencies.
Virtual currencies. Like fiat currency, virtual currencies such as Bitcoin, Litecoin, and Ether are intended as a medium of exchange that enables two parties to transact business. But there are important differences: No physical coins or bills. Virtual currencies exist only in computer code. Except for visual representation of Bitcoin and altcoins in advertising and displays, and coin-like tokens that may be produced for marketing purposes, there are no actual coins or bills. Not legal tender. Virtual currencies are not legal tender and are not issued or backed by a government. However, many virtual currencies, which are called convertible virtual currencies, can be redeemed for fiat currency on a number of exchanges. No regulation. Virtual currencies are not regulated by any government agency or authority. However, regulation is being considered, especially where virtual currencies function as securities when they’re used to raise capital and when traded on exchanges.

While the platform has started accepting account registrations and deposits/withdrawals of cryptocurrencies, its services do not yet cover the entirety of the US market, as the following states have been excluded from its support as of the time of writing the review (September 19, 2019):
Typically valued for less than one dollar, Loopring prices are now over $3 a share.