---
title: "intervalDidStart(for:)"
framework: Device Activity
role: symbol
role_heading: Instance Method
platforms: [iOS 15.0+, iPadOS 15.0+, Mac Catalyst 15.0+]
path: "deviceactivity/deviceactivitymonitor/intervaldidstart(for:)"
---

# intervalDidStart(for:)

Indicates that the device activity interval started.

## Declaration

```swift
func intervalDidStart(for activity: DeviceActivityName)
```

## Parameters

- `activity`: The name of the activity.

## Discussion

Discussion An activity starts when someone first uses the device within the activity’s scheduled time interval. In other words, the system only invokes this method when the device is in use.

## See Also

### Monitoring Scheduled Intervals

- [intervalDidEnd(for:)](deviceactivity/deviceactivitymonitor/intervaldidend(for:).md)
- [intervalWillEndWarning(for:)](deviceactivity/deviceactivitymonitor/intervalwillendwarning(for:).md)
- [intervalWillStartWarning(for:)](deviceactivity/deviceactivitymonitor/intervalwillstartwarning(for:).md)