If I brought some stocks with Robinhood app in 2017 and didn't sell any units, do I need to report my purchase on my 1040?

[yatoshura]

Does buying stocks on my own using apps like Robinhood require me to report anything on my 1040?

[LisaBr]

No, you will not report your stock purchases unless they were sold in 2017.

You will report the purchase price paid for these stocks when they are sold.  At that time, you will be issued a 1099-B that will report the sales from your brokerage firm (Robinhood).