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.

TradeStation - Whether you trade stocks, ETFs, options or futures, TradeStation’s award-winning tools and...

quantra - A public API for quantitative finance made with Quantlib

Questrade - Questrade IQ Mobile is everything you need to trade stocks - right in the palm of your hand.

Backtrader - Backtrader is a complete and advanced python framework that is used for backtesting and trading.

Merrill Edge - Merrill Edge is a brokerage platform that helps in investing, provides advisory consultations, and other services.