Micro investment apps such as, Acorns, round up the purchases you make with your linked credit or debit card to the nearest dollar and add it into an investment portfolio. So, if you spend $1.78 on a pack of Orbit gum at the gas station, the app reads the purchase as $2 and transfers 22¢ into your investment account. You are also able to customize your risk profile as well as contribute sums separate from those taken from your purchases. Ditch the piggy bank and start investing!