Which is the best app for someone who doesn’t know anything about investing?

[karlmarx]

Ah, you're saying that Medallion's returns are sus! Well I guess only insiders will know whether it's T-rex or a raccoon.

Personally I'm not interested in the quants approach to investing/trading. Maybe my choice of citing Medallion was a bad example, but I do believe there are those who succeeded in taking the quants approach.