Choose a versatile POS system that can handle both in-store and online transactions. Systems like Square or Shopify POS are cloud-based and can seamlessly integrate with your online store.

Utilize a robust e-commerce platform like Shopify, WooCommerce, or Magento for your online store. These platforms offer various customization options and integrations with POS systems.

Implement an inventory management system to track stock levels across both online and offline channels. Tools like TradeGecko or DEAR Inventory can synchronize inventory data in real-time.

Use a CRM system to manage customer interactions and data. Salesforce or HubSpot CRM can help you track customer preferences and behaviors across channels.

Integrate an analytics platform like Google Analytics or Adobe Analytics to track customer journeys and behaviors across online and offline touchpoints.

Implement RFID or barcode scanning technology for efficient inventory management and checkout processes in-store.

Implement a customer loyalty program software to reward repeat purchases and encourage customer retention. LoyaltyLion or Smile.io are popular choices that can integrate with both online and offline channels.

Consider integrating an ERP system like NetSuite or SAP for comprehensive management of business processes including finance, procurement, and supply chain management.