Did you miss the whole fiasco surrounding Robinhood over the past couple of months? Their reputation is in the toilet and they've been shunned by a large portion of the financial sector, which isn't exactly what you want from a brokerage who you want to cover your investments.

Due diligence can start as simply as typing "robinhood scandal" in google. They're known for using addictive and predatory tactics so using the app first as a means of doing DD isn't necessarily wise.