Fitness: auto-start Outdoor Walk workout with navigation

[eric-ormoni]

Summary

Automatically start (or reliably align with) an Outdoor Walk workout in Apple’s Fitness / Activity ecosystem when the user begins a Random Walker navigation session—in the spirit of tapping Outdoor Walk in the Watch Workout app, but triggered from Random Walker flow.

Motivation

• One less manual step before walking.
• Energy, duration, Heart Rate, GPS track, rings, etc. accumulate in Health where users already expect them.
• Tighter story between “walking with the app” and “logged as formal exercise.”

Scope (to refine)

• HealthKit workouts: explore HKWorkout, HKWorkoutBuilder / workout session APIs, and outdoor-walk distinction (activity type .walking, location type outdoor where applicable via configuration or metadata per current Apple APIs).
• Platforms: Random Walker ships iOS + Apple Watch. Workout-session authority often lives on watchOS; define whether iOS kicks off paired Watch session, only requests Health permission and defers recording to Watch companion, or both.
• Lifecycle: tie start/end (and pause semantics if any) to existing start / stop / completion semantics in-app (see navigation + history docs—avoid orphaned workouts if user cancels immediately).
• Permissions & copy: clarify new HealthKit usage / NSHealth*UsageDescription strings if workout write or sharing not already sufficient.

Risks / product questions

• User may prefer not polluting Fitness with workouts when they’re only scouting a route—or may want explicit opt-in.
• Duplicate workouts if Apple Watch independently starts Outdoor Walk manually.
• Background delivery and battery implications on Watch.

Acceptance (draft)

• Beginning a structured “walk/navigation session” in Random Walker offers or performs an Outdoor Walk linkage consistent with chosen product rule (always / ask / never).
• Workout reliably appears in Fitness / Activity with sane start/end timestamps relative to UI state.
• Permissions and failure states are handled without blocking unrelated app features silently.
• Brief developer note in docs/ (walking-pace, history, or in-app navigation—whichever best fits the final design).

Notes

• Depends on current HealthKit entitlements (RandomWalkerWatch embedding, existing walking-pace ingestion). Coordinate with whichever target already owns health writes.