You can trade cryptocurrencies with IG using a CFD account, which are derivative instruments that allow you to guess on whether the value of your selected cryptocurrency will rise or decline. Prices are expressed in traditional currencies, such as the US dollar, and you never possess the cryptocurrency.
CFDs are leveraged products, meaning you can open a position for a portion of the trade's entire value. Leveraged products can increase your profits, but they can also increase your losses if the market goes against you.