• Support Proc object in :conditions option of associations @bradly
• input_field supports html5 component @nashby

• Make field_error_proc configurable @dfens

• Remove deprecation warnings related to Relation#all from Rails 4.
• Form builder can be used outside the context of a controller @jasonwebster
• Skip pattern attribute when using validates_format_of with :without option @glebm

• Support to Rails 4.
• Removed deprecated methods.
• SimpleForm no longer sets the size attribute automatically and the default_input_size setting is now deprecated.
• Support to aria-required attribute to required fields @ckundo

Please check v2.1 for previous changes.