What are the best tools of 2019 that helped you save time and energy?

1) Ngrok: I've been using ngrok to give my local backend development server a live a URL that my front end mobile apps can access (https://my-super-sweet-project.ngrok.io)

2) React Native: Really love what I've been able to do with React Native since I started using it within the last several months. In the past I've dabbled in native android and ios development, along with hybrid development using Apache Cordova, but React Native really seems to offer the best of both worlds. Maybe isn't a perfect solution, but it's pretty damn good.