Giftbit Payment API - Stripe for gift cards

And We Evolve - Subscription box for stylist-picked secondhand clothing

Felt for iPhone - Handwritten cards for the modern world

Trove Market - The easiest way to buy/sell used + vintage furniture

Raise - The easiest way to save money on the go

Wallapop - Wallapop is a free mobile app that acts as a virtual flea market for buying and selling items locally.