Phased release ios

iOS Phased Release

Instructions

Apple's Phased Release for Automatic Updates throttles how many auto-updating devices receive a new version over a 7-day window. It's mandatory for safe iOS rollouts and complements (does not replace) server-side feature flags.

1. How the 7-Day Ramp Works

Day	Auto-update devices that can receive	Cumulative
1	1%	1%
2	2%	2%
3	5%	5%
4	10%	10%
5	20%	20%
6	50%	50%
7	100%	100%

Important: any user who manually updates (App Store → search → Update) gets the new version immediately, regardless of phase. Phased release only affects auto-updates.

2. Enable with deliver

lane :release do
  api_key = app_store_connect_api_key(...)
  deliver(
    api_key: api_key,
    submit_for_review: true,
    automatic_release: false,
    phased_release: true,
    force: true,
  )
end

Alternatively enable in App Store Connect → My App → Version → Phased Release for Automatic Updates → Release update over 7-day period.

3. States

• INACTIVE — not started (version in review or pending developer release).
• ACTIVE — ramp in progress.
• PAUSED — ramp halted at the current percentage; developer action required.
• COMPLETE — 100% of auto-updaters covered.

State transitions are one-way forward (ACTIVE → PAUSED → ACTIVE → COMPLETE); you cannot rewind.

4. Pause the Ramp

Via UI (Connect → version → Pause Phased Release) or via the App Store Connect API:

curl -X PATCH \
  "https://api.appstoreconnect.apple.com/v1/appStoreVersionPhasedReleases/$ID" \
  -H "Authorization: Bearer $JWT" \
  -H "Content-Type: application/json" \
  -d '{
    "data": {
      "type": "appStoreVersionPhasedReleases",
      "id": "'"$ID"'",
      "attributes": { "phasedReleaseState": "PAUSED" }
    }
  }'

Fetch the $ID:

curl -s "https://api.appstoreconnect.apple.com/v1/appStoreVersions/$VERSION_ID/appStoreVersionPhasedRelease" \
  -H "Authorization: Bearer $JWT" | jq -r .data.id

5. Resume the Ramp

Set phasedReleaseState back to ACTIVE. The schedule resumes from the current step, not the start.

6. Release to All Users

If a build is healthy and you want to skip the remaining days:

curl -X PATCH \
  "https://api.appstoreconnect.apple.com/v1/appStoreVersionPhasedReleases/$ID" \
  -d '{"data":{"type":"appStoreVersionPhasedReleases","id":"'"$ID"'",
       "attributes":{"phasedReleaseState":"COMPLETE"}}}'

7. Interaction with Rollback

Pausing the phase does not pull the binary from users who already received it. For a true rollback you must:

1. Pause the ramp.
2. Submit the previous source as a new build (you cannot resubmit the same binary).
3. Request expedited review.
4. Users on the regressed build update to the new (formerly old) version.

Server-side kill switches via feature flags are always faster than any store-level rollback.

8. When to Disable Phased Release

Rare but legitimate cases:

• Security hotfix where every hour of exposure is expensive — disable phased, release to all at once.
• Compliance deadline (GDPR, tax, age-gating) that requires 100% rollout on a specific date.
• App uses server-side feature flags with per-user rollout already, so the binary can be broadcast.

Disable by unchecking the option in Connect or passing phased_release: false.

9. Monitoring During a Phased Release

Track by day:

• Crash-free sessions at the current phase vs the previous version.
• New crashes not present on the prior version (first_seen = this_version).
• Adoption curve matches Apple's expected ramp; deviations suggest auto-update disabled on a cohort.
• App Store ratings on this version.

Integrate with Firebase Crashlytics, Sentry, or App Store Connect's Metrics API.

10. Metrics API Sample

curl -s "https://api.appstoreconnect.apple.com/v1/apps/$APP_ID/perfPowerMetrics" \
  -H "Authorization: Bearer $JWT" -H "Accept: application/vnd.apple.xcode-metrics+json"

11. Checklist

• phased_release: true set on every production deliver lane.
• Pause/resume commands rehearsed; JWT generation scripted.
• Server-side kill switches in place for features where phased release is too slow.
• Monitoring dashboard filtered to the current version for the full 7 days.
• Manual-update bypass understood and communicated to stakeholders.
• Decision documented whenever phased release is skipped, with justification.