"Investing" and "Stock Trading" are incompatible in the same sentence, unless combined with a phrase like "does not involve".
You can buy and hold, or "Invest", on any platform which, in my opinion, has to meet three minimum requirements: It should offer commission-free trading on a variety of low-cost index funds, it should offer a variety of investment account types (at minimum, taxed accounts, Traditional IRAs, and Roth IRAs), and it should be stable.
Robinhood only meets one of these three criteria. There are dozens of other brokerages out there which do meet all of these criteria: TDAmeritrade, Schwab, Vanguard, and Chase are four great ones.
Robinhood is on the same level as a betting app for sports; so, fine; use it if that's what you want. But do not even mention the word "Invest" in the same sentence as Robinhood; its grossly irresponsible.