My client has recently added more varients of pack sizes for their products... e.g. they sell and energy bar with 5 varients. Users can buy a single bar, a 3-pack, 9-pack, 15-pack and a 24-pack.
Is there an app out there that can help us communicate the savings the user will be making if they purchase a pack with more energy bars?
For example, see the 'pack sizes' for this product: https://veloforte.cc/products/avanti
Is there a way for us to have 'X% savings' when they click each varient?
What you're looking for are known as 'Quantity Break' apps. These apps generally allow you to set percentage or fixed amount discounts on selected products/collections that the customer will be able to see on the product page. There are a variety options you can find in the Shopify App Store.
If there is anything else I can help you with, please let me know.