Newfag here. What do you /biz/ people use to buy and sell stocks? And what do you guys usually trade, stocks, currency etc?
With rates as low as they are, nobody is making money off cash balances. Margin yes, but who would borrow at those usurious rates just for free trades.
Truth is, they make money off the trade prices. They'll strive to buy at the lowest price of the day (below vwap; volume weighted average price) and sell to you at the highest price (above vwap). Or they can just sell the order flow to a trading firm who will do the same.
I use a local paid platform, exclusive to Brazilian markets.
I trade futures (index and dollar futures) and sometimes stocks. Daytrade only.
Planning on joining IFundTraders and trade aapl with their platform, Fusion. Aapl is a wonderful stock to daytrade.