> ## Documentation Index
> Fetch the complete documentation index at: https://docs.nativeline.ai/llms.txt
> Use this file to discover all available pages before exploring further.

# Capabilities

> Enable advanced iOS features like Push Notifications and Sign in with Apple

# Capabilities

Capabilities are advanced iOS features that require special entitlements from Apple. They enable powerful functionality but require additional setup.

## What Are Capabilities?

Capabilities are different from permissions:

| Permissions                       | Capabilities                  |
| --------------------------------- | ----------------------------- |
| Runtime access (camera, location) | System-level features         |
| User grants access                | Requires Apple provisioning   |
| Works immediately                 | Needs developer account setup |

***

## Available Capabilities

### Push Notifications

Send alerts to users even when the app isn't open.

**Requirements:**

* Apple Developer account (\$99/year)
* APNS (Apple Push Notification Service) setup
* Server to send notifications (or service like Firebase, OneSignal)

**Use cases:**

* New message alerts
* Order updates
* Reminders
* Marketing (with user consent)

### Sign in with Apple

Let users sign in with their Apple ID.

**Requirements:**

* Apple Developer account
* Properly configured entitlements

**Use cases:**

* User authentication
* Required if you offer other social sign-ins (Google, Facebook)

**Benefits:**

* Privacy-focused (can hide email)
* Quick, trusted sign-in
* No password to remember

### HealthKit

Access health and fitness data from the Health app.

**Requirements:**

* Apple Developer account
* Specific usage descriptions
* Health data review by Apple

**Use cases:**

* Fitness tracking apps
* Health monitoring
* Workout apps
* Nutrition apps

### HomeKit

Control smart home devices.

**Requirements:**

* Apple Developer account
* MFi (Made for iPhone) certification for accessories

**Use cases:**

* Home automation apps
* Smart device control

### CloudKit

Store data in iCloud.

**Requirements:**

* Apple Developer account
* CloudKit dashboard setup

**Use cases:**

* Sync data across user's devices
* Server-free data storage
* Sharing between users

### In-App Purchases

Sell content within your app.

**Requirements:**

* Apple Developer account
* Products configured in App Store Connect
* Review process

**Use cases:**

* Premium features
* Subscriptions
* Consumables (coins, credits)
* Digital content

### App Groups

Share data between your apps or app extensions.

**Use cases:**

* Widget data sharing
* Share extension
* Multiple apps from same developer

### Background Modes

Run tasks in the background.

**Types:**

* Audio (music apps)
* Location (navigation)
* Background fetch (refresh data)
* Remote notifications

**Note:** Apple scrutinizes background modes. Only enable what you actually need.

***

## Enabling Capabilities

### In Nativeline

1. Open your project
2. Go to **Settings** → **Capabilities**
3. Toggle on the capabilities you need
4. Complete any additional setup (API keys, etc.)

### Via Chat

You can ask:

```
Enable Push Notifications capability for this app
```

<Note>
  Some capabilities require additional setup in Apple Developer Portal or App Store Connect.
</Note>

***

## Apple Developer Account

Most capabilities require an Apple Developer account:

**Cost:** \$99/year

**What you get:**

* Ability to use capabilities
* TestFlight distribution
* App Store submission
* Access to developer resources

**Sign up:** [developer.apple.com](https://developer.apple.com)

***

## Setting Up Common Capabilities

### Push Notifications Setup

<Steps>
  <Step title="Enable in Nativeline">
    Settings → Capabilities → Push Notifications → Enable
  </Step>

  <Step title="Create APNS Key in Apple Developer Portal">
    Certificates, IDs & Profiles → Keys → Create Key for APNS
  </Step>

  <Step title="Download the .p8 key file">
    Keep this secure — you can only download once
  </Step>

  <Step title="Configure push service">
    Use Firebase, OneSignal, or your own server with the APNS key
  </Step>

  <Step title="Enter configuration in Nativeline">
    Add your Key ID, Team ID, and .p8 file
  </Step>
</Steps>

### Sign in with Apple Setup

<Steps>
  <Step title="Enable in Nativeline">
    Settings → Capabilities → Sign in with Apple → Enable
  </Step>

  <Step title="Configure in Apple Developer Portal">
    Identifiers → Your App ID → Enable "Sign in with Apple"
  </Step>

  <Step title="Add to your UI">
    Ask AI: "Add Sign in with Apple button to the login screen"
  </Step>
</Steps>

### HealthKit Setup

<Steps>
  <Step title="Enable in Nativeline">
    Settings → Capabilities → HealthKit → Enable
  </Step>

  <Step title="Specify data types">
    Configure which health data types your app reads/writes
  </Step>

  <Step title="Add usage descriptions">
    Explain why you need each type of health data
  </Step>

  <Step title="Request authorization in app">
    Ask AI: "Request HealthKit authorization for step count and workouts"
  </Step>
</Steps>

***

## Capabilities and App Review

Apple reviews capability usage. They may reject apps that:

* Don't actually use enabled capabilities
* Use capabilities inappropriately
* Don't explain capability usage clearly
* Request sensitive data without justification

### HealthKit Specific

HealthKit apps face extra scrutiny:

* Must have clear health/fitness purpose
* Need detailed privacy policy
* May require additional review time

### Sign in with Apple

If your app offers third-party sign-in (Google, Facebook), you **must** also offer Sign in with Apple. This is an App Store requirement.

***

## Troubleshooting

<AccordionGroup>
  <Accordion title="Push notifications not working" icon="bell-slash">
    Common issues:

    * APNS key not configured correctly
    * Bundle ID doesn't match
    * Device not registered for push
    * Check certificate expiration

    Test with Apple's Push Notifications Console first.
  </Accordion>

  <Accordion title="Sign in with Apple fails" icon="apple">
    Check:

    * Capability enabled in Developer Portal
    * Bundle ID matches exactly
    * Entitlements file is correct
    * Testing on real device (Simulator has limitations)
  </Accordion>

  <Accordion title="HealthKit authorization denied" icon="heart-pulse">
    * User must explicitly grant access
    * Check usage description is clear
    * Some data types require additional justification
    * Test on real device (Simulator has limited Health data)
  </Accordion>

  <Accordion title="Capability not appearing" icon="eye-slash">
    * Ensure Apple Developer account is connected
    * Check Team ID is correct
    * Regenerate provisioning profiles
    * Some capabilities need explicit enabling in Developer Portal
  </Accordion>
</AccordionGroup>

***

## Related

<CardGroup cols={2}>
  <Card title="Permissions" icon="lock" href="/features/permissions">
    Runtime permissions (camera, location, etc.)
  </Card>

  <Card title="Apple Developer Account" icon="apple" href="/publishing/apple-developer-account">
    Setting up your developer account
  </Card>
</CardGroup>