I'm curious, is CEX.IO a free platform for trading cryptocurrencies? I've heard about its reputation and features, but I'm unsure if there are any hidden fees or charges that I should be aware of. As a cryptocurrency enthusiast, I'm always looking for cost-effective options when it comes to buying, selling, and exchanging digital assets. Can you clarify if CEX.IO offers a free service, or if there are specific fees associated with using its platform?