Millennials hire computers to invest their money

[...] their disruption potential to traditional wealth advising is massive, said Alois Pirker, research director at the Aite Group, which studies wealth management trends.

Acorns also helps customers squirrel away savings by rounding each purchase a customer makes with their linked credit or debit card to the nearest dollar and investing the change.

[...] investors who want to do everything themselves can open an account at a discount brokerage like Charles Schwab or Fidelity and pay only the fund fees, which for some big exchange traded index funds can be just 0.05 percent.

By comparison, Vanguard's total market fund has $385 billion by itself, and the wealth management market is measured in the trillions.

While growing in popularity, robo-advisers are not suitable for everyone.

Because the portfolios are managed by computers, investors are at the mercy of the algorithms that created them.

Because they are new, these algorithms have not been tested in a recession or a severely stressed market like the one seen during the financial crisis.