The 'Suppliers' app by CloudCart allows you to add a supplier from whom you take your products, to assign specific suppliers to specific products as well as to compare the supplier price to the one in your store.
Microinvest Warehouse Pro is a flexible system for managing stocks and cash flows of companies. The program allows to control all processes related to the management of production and trade activities.
Asbis B2B IT4profit is a distributor of a wide range of IT products and through this app you can automatically import in your store multiple products from the platform. It is great for starting a dropshipping service focused on IT products.