Robinhood - Free stock trading service.
The Brex API - Brex credit cards and business accounts help startups scale fast, and Brex’s API can make you even faster.
Alpaca Data API - Free real-time stock market data API
Setu - Setu’s APIs and software is used by hundreds of businesses from startups to large enterprises to reimagine onboarding, payments, deposits, lending and data empowerment for their end customers.We’re hiring across the board!
SparkFin - Learn the markets for free, profit forever.
Stripe iOS SDK - Accept both Apple Pay and credit card payments easily on iOS