How to get theta on iPhone?

Could you please elaborate on the steps involved in acquiring Theta tokens on an iPhone? As a cryptocurrency enthusiast, I'm curious about the process and whether it's a straightforward one. Could you walk me through the necessary apps to download, any potential exchanges to use, and any security measures I should be aware of? Additionally, would you recommend any specific wallets for securely storing my Theta tokens once I've acquired them? Understanding the entire process from start to finish would be invaluable.