Describe the business problem
Write a short statement of what users cannot do efficiently today and how a successful mobile workflow would help. Avoid starting with a long unprioritized feature wish list.
Identify people and permissions
List customer, staff, manager, distributor and administrator roles; the screens and data each role may use; and any formal approval process.
Identify systems and data
Document existing software, API availability, payment gateways, notifications, offline constraints, retention needs and data ownership expectations.
Define the delivery boundary
Confirm essential screens, design approvals, testing devices, deployment responsibilities, training requirements and support after release.