How can I make $100 a day on my phone?

I'm curious to know, how feasible is it really to earn $100 a day solely through the use of a smartphone? Are there specific cryptocurrency trading or financial investment apps that can consistently deliver such returns? And what about the risks involved? Wouldn't it require a significant amount of capital or specialized knowledge to turn such a profit consistently? I'm eager to learn more about the practicality and potential pitfalls of this approach.