Based on our record, Bootstrap.build seems to be more popular. It has been mentiond 1 time since March 2021. We are tracking product recommendations and mentions on various public social media platforms and blogs. They can help you identify which product is more popular and what people think of it.
I would highly recommend https://bootstrap.build/ to configure a custom theme for Bootstrap. A different theme really changes things up, while keeping everything that is great about Bootstrap. Source: almost 2 years ago
Bootstrap Magic - Create your Bootstrap 4.0 themes easily with magic
Invision - Prototyping and collaboration for design teams
BootStarters - Huge open source collection of free themes for Bootstrap 5
Mockuuups Studio - Fast and easy way to create product mockups on macOS, Windows and Linux.
Shuffle for Bootstrap - Bootstrap drag and drop builder for busy developers.
Craftwork - A collection of User Interface resources made by Craftwork