- Sign in (or create an account) in Settings → Account. Plans are linked to your 1kr account, so they also work on your other phones.
- Open Plans, choose a plan and tap Subscribe.
- Confirm with Face ID, Touch ID or your Apple ID password. You see "Thank you! Your plan is active."
Payment is charged to your Apple ID. Subscriptions renew automatically unless cancelled at least 24 hours before the end of the current period. You can manage or cancel them in your Apple ID settings.
Restore Purchases: on a new iPhone, or if the app doesn't show your plan, tap it to link your App Store subscription to the account again.
Manage subscription: change or cancel the subscription (or in the iPhone's Settings → Apple ID → Subscriptions).
Plans can also be bought on the website; those are managed there. Problems: see "Subscription messages on iPhone".