With smart objects, you can apply the same edit across multiple screens at once.
Once you have set an element within your template to be a smart object, anytime you edit it, the same change will be applied anywhere that element is found throughout the template.
Applying Smart Objects
To create a smart object, first select an element within your template screen. Then click on the Smart Objects icon, followed by New Smart Object.
The following pop-up will appear enabling you to create a smart object.
Once you've created the smart object, you will be asked if you want it applied anywhere else where its found throughout the template.
Screens where the smart object exists will have the icon displayed in the screen's thumbnail.
You can locate all of your saved smart objects at once by clicking on the Smart Objects Icon in the left hand side of the template editor.