Robinhood - Free stock trading service.
Alpaca Data API - Free real-time stock market data API
Scout Finance - Free finance app that's like having a Bloomberg in your pocket. Download:
data.world - The social network for data people
Spark Mail - Spark helps you take your inbox under control. Instantly see what’s important and quickly clean up the rest. Spark for Teams allows you to create, discuss, and share email with your colleagues
Gist - Create simple, beautiful data driven applications