Bootstrap Magic - Create your Bootstrap 4.0 themes easily with magic
Codespace - A beautiful cross-platform code snippet manager
HackerThemes - Bootstrap 4 themes and tools for web developers
CodeMyUI - Handpicked code snippets you can use in your web projects
Bootstrap 4 Cheat Sheet - An interactive Bootstrap 4 cheat sheet
Creative Tim - Awesome Bootstrap freebies and templates to build better websites