Thousands of pro-democracy protesters are taking to the streets of Hong Kong ahead of a national holiday on Wednesday, and they're using a messaging app to keep in touch and defy censorship. FireChat is a messaging app built by the San Francisco-based company Open Garden, which creates products facilitating a more open, decentralized internet. What makes the app fascinating is that it doesn't require the internet for local chat, instead allowing people to connect via Bluetooth. When you first download FireChat, the app doesn't let on that it has become a hub for pro-democracy protesters around the world. Instead, the...