Define the shopping journey
Include search, product variants, stock information, basket, checkout and order status. Decide which features customers genuinely need on mobile. Existing platform APIs can reduce repeated work but may require adaptation. Clarify whether loyalty, promotions, multiple currencies or subscriptions belong in the first release.
Connect commerce operations
Payment, inventory, shipping, customer service and reporting need consistent data. Verify the available integrations before estimating. Test failures such as a declined payment or a stock change during checkout. Avoid duplicating business rules in the app where the existing commerce system should remain the source of truth.
Measure the value of the app
Consider repeat purchase, retention and checkout completion as well as downloads. Plan release, support and analytics alongside implementation. A mobile website may be sufficient for some businesses; a dedicated app should address a clear use case. Prioritise the improvements that make buying and post-purchase service easier.