translation.en: We started with paper, we moved to a mobile application, web, and now even a controllable thermostat, and for the last five years we've been running the largest behavioral science experiment in the world.
translation.zh: 我们从纸张开始，然后是手机应用， 网络，现在甚至是可控恒温器， 在过去的五年中，我们已经开始 启动世界上最大的行为科学实验。