User can manage Wishlist by adding & removing the products.
The product is added in the Wishlist from the Product listing page or from the Product details page by clicking on Wishlist icon .
You can add to cart by clicking on Cart icon .
To clear whole Wishlist, tap on Clear All All the added products will be removed.
Note: You can make changes to the Wishlist option from the backend configuration. For that navigate to Stores -> Configuration -> Customers -> Wish List -> Under the ‘General Option’, you can Enable/Disable the Wishlist option for Mobile app.