RookieUp Career Bootcamps - Tools to help designers build great portfolios and get jobs.
Sketch Mirror - Preview your iOS designs directly on your devices
The PM Toolkit - Process and tools to run human-centered projects
Crystal: Sketch Mirror for Android - Crystal: Sketch Mirror for Android is an application that is designed for viewing your sketch designs in real-time, navigate prototypes and download content related to the sketches for offline viewing.
Scrimba - Interactive coding screencasts created in an instant
Flowkit - Sketch library for user flows/content maps/annotations