7 Best Investment Apps in USA

1. Fidelity

2. E*TRADE

3. Merrill Edge

4. J.P. Morgan Self-Directed Investing

5. Acorns

6. TD Ameritrade

7. Vanguard

How much cash will I need to get going? You can establish an investment portfolio with little money—even just your spare change, in fact—thanks to micro-investing applications like Acorns and Stash.

For instance, Acorns sweeps purchases from a linked credit or debit card account, rounds them up to the next dollar, and then invests the spare change. Similar opt-in functionality is available from Stash, which deposits money into users' accounts after rounding up transactions.