QuantConnect - QuantConnect provides a free algorithm backtesting tool and financial data so engineers can design algorithmic trading strategies. We are democratizing algorithm trading technology to empower investors.
TradingView - The best charting tool for crypto and stocks
quantra - A public API for quantitative finance made with Quantlib
eToro - The social investment network that connects traders from around the globe and enables them to share...
Backtrader - Backtrader is a complete and advanced python framework that is used for backtesting and trading.
Robinhood - Free stock trading service.