On March 20, 2020, as part of its response to the coronavirus pandemic, Shopify announced it would enable the gift card feature to all of its plans at no extra charge. 

This change is effective for the foreseeable future, though Shopify has not announced a solid end date for this change.

This means all Shopify plans are compatible with ShopKeeper entire suite of gift card apps

Note that you will need to complete a few setup steps to enable gift cards on your store if you don't have it already. Click here for directions.