External Purchases (US Web Checkout)

On the US storefront, apps may link out to a web checkout for digital goods using the StoreKit External Purchase Link entitlement — and as of mid-2026, court orders have Apple's commission on those purchases at 0%, with the fee case still moving through district court. This is the largest indie revenue unlock of the era, and it is reversible by a ruling — so the engineering rule is: ship it now, architect it so a commission can be flipped on later.

Verify current state before relying on this: the entitlement terms, the commission rate, and the litigation status have each changed more than once. Treat every number here as "true as of 2026-07, re-check."

When This Skill Activates

• "Add a web checkout / Stripe / external purchase link" for digital goods
• Deciding IAP vs web checkout for a US-heavy revenue base
• The store-growth audit flags P8.4
• Reviewing an app whose external links might be non-compliant (wrong storefront, no entitlement)

The rules of the road

• US storefront only — elsewhere Guideline 3.1.1 still applies (EU/JP/KR have separate entitlements/terms; don't extrapolate from the US).
• Entitlement required: com.apple.developer.storekit.external-purchase-link + matching Info.plist declaration — a bare Link("Buy", …) without it is still a rejection (see app-store/rejection-handler §3.1.1).
• Present the link per the entitlement's UI terms (StoreKit's ExternalPurchaseLink / disclosure sheet where required). Don't dark-pattern the IAP option away if you keep both.
• Purchases made on the web are your customer relationship — payment processor, refunds, taxes; Apple's merchant-of-record role no longer applies.

Architecture: the commission flip

Design so that a future "Apple takes N% of external purchases initiated in-app" ruling changes a config value, not your codebase:

• ✅ Route every in-app-initiated web checkout through one link-out service that stamps the session (source=app, timestamp, storefront) — web-organic checkouts stay unstamped. If a commission returns, it applies to a knowable, logged subset.
• ✅ Keep a single CommissionPolicy (remote-configurable): rate, applies_to, effective_date. Report/accrue against it from day one — at 0% it's just a counter.
• ✅ Log day-one analytics: link taps → checkout starts → completions, vs the IAP funnel. The conversion drop through a web checkout (Apple's sheet, Safari hop, payment form) is real; whether 0% beats IAP's frictionless 85–70% is an empirical per-app question.
• ❌ Scattering openURL("https://…/buy") calls through features — un-auditable, un-flippable.
• ❌ Ripping out StoreKit. Keep IAP as a fallback path (non-US storefronts still need it, and some US users convert better in-sheet).

Decision sketch

Situation	Lean
Subscriptions, US-heavy, ARPU high enough to absorb processor fees + your own support	Web checkout for new subs; keep IAP for the rest of world
Impulse-priced consumables/unlocks	IAP — checkout friction eats more than 15–30% commission
Existing subscriber base on IAP	Don't force-migrate; offer web at renewal decision points
B2B/prosumer, invoicing needs	Web checkout regardless of commission math

Output Format

Status: entitlement present? · storefront scope correct (US-only gating)? ·
link-out service centralized? · CommissionPolicy flippable? · funnel analytics live?
Verdict + the one next step.

References

• https://developer.apple.com/documentation/storekit/externalpurchaselink
• https://developer.apple.com/support/storekit-external-entitlement-us/
• https://developer.apple.com/app-store/review/guidelines/#in-app-purchase
• Related skills: app-store/rejection-handler (the non-entitled rejection pattern), generators/subscription-lifecycle, monetization (pricing), growth/store-growth-audit