Too Long; Didn't Read
An application can only be as good as the features it is providing for its end-users. When time is of the essence, these are the gems I reach for. Devise is still the go-to gem for authentication in most Rails apps. Kaminari is a simple yet powerful approach to adding pagination into your applications. Bootstrap Email allows you to use Bootstrap-like HTML structures, use a Bootstrap like design, and inline the CSS to work in most email browser/apps.