devise_auditable is a plugin for Devise that adds a audit log support to Devise.

Add devise_auditable to your Gemfile

gem 'devise_auditable'

Run the installer

rails g devise_auditable User

Add the auditable key to your devise user model

class User < ActiveRecord::Base
  devise :database_authenticatable, ..... , :auditable
end

Optionally, you can add a has_many relationship to your devise model.