Yes, a well-developed POS software system can support omnichannel selling. With omnichannel functionality, your POS system can seamlessly integrate and sync data across all sales channels, be it physical stores, eCommerce websites, mobile apps, or third-party marketplaces. This ensures:

Real-time inventory across all platforms

Unified customer data and purchase history

Consistent pricing offers and promotions 

Streamlined order fulfillment(click & collect, in-store returns for online orders, etc.)