Don't know how to invest your extra cash? Let a robot do it for you.

Let's say you have a pile of cash that you're ready to invest.

If you're like me, you probably don't want to spend all your time with your eyes glued to a screen, actively trading on Robinhood. You want your money to grow, but you don't want to think about it all the time. Maybe the idea of interacting with an investment professional gives you anxiety, or the fees sound like a lot.

You're not alone.

A study of 3,000 U.S. adults conducted by Vise, a technology-powered investment management platform built for advisers, that was given exclusively to USA TODAY found that the biggest barrier to working with an adviser is concern about how much it would cost (43%).

Michelle Shen is a Money and Tech reporter
Michelle Shen is a Money and Tech reporter

Here's what I did: I skipped the personal investment adviser and got a robot to build my portfolio.

Roboadvisers, digital apps that use algorithms to build investment portfolios​​​​​​, are an increasingly popular vehicle for investing, especially for young adults who want a tool that is uncomplicated and mobile-friendly.

You can download an app and fill out a survey about yourself with questions like your age, income and risk tolerance. Based on those responses, roboadvisers generate a portfolio of stocks and bonds for you to maximize your long term returns.

These investment vehicles can scale dramatically with little marginal cost because the portfolio is generated by algorithms. Since they cut out the human element of investing, they can service millions of customers at once with just a few lines of code.

Many roboadvisers are designed with young investors in mind, specifically millennial and Gen Z clients.

Gen Zers, born between 1997 and 2012, began entering the workforce shortly before the COVID-19 pandemic hit and when unemployment rates were at historic lows. Jobless rates subsequently skyrocketed and then have leveled off. And those workers are starting to save for retirement at an unprecedented young age, according to Transamerica Center for Retirement Studies, a nonprofit organization.

Similar to millennials, born between 1981 and 1996, these young Americans are saddled with student loans and credit card debt but want to invest for retirement and build up savings.

Study reveals: Student debt is a potentially crippling liability for college grads

"Millennials and Gen Z grew up digitally native, and they expect to be able to manage their money the same way they order stuff from Amazon or call a car on Uber," says Kate Wauck, chief communications officer at Wealthfront, a roboadvising company. "These young investors don’t want to have to pick up the phone or walk into a stuffy office to manage their money."