Acorns is different from the apps listed above in that it can earn you more money by investing some of the money you already have.
So instead of leaving any extra cash — beyond, for example, what you keep in your emergency fund and what you need in your checking account — to sit in a regular savings account where it earns practically zero interest, Acorns will invest it for you in diverse portfolios created by experts and designed to optimize returns for a given level of risk. Note: Investments by nature aren't a sure thing, so make sure you're OK with a bit of a risk and are only working with money you know you could lose.
Here's how it works: Using the app, you can set up recurring investments and have a certain amount of money automatically sent to your Acorns account each day, week or month, or you can make one-time investments.
Acorns also gives you the option of investing your "spare change," meaning it will round up your purchases to the nearest dollar and invest small amounts of money you probably wouldn't miss. These automatic savings will stack up faster than you may think and investing mindless.
Cost: $1 per month
Read more about Acorns.