Will a user receive a push notification triggered by 'First Install' if they downloaded the app but haven't opened it?

No, a user will not receive a push notification in this scenario.

In Pushwoosh, First Install is a default Date tag that records "the time when a device was registered for notifications for the first time" — it is set by the SDK at the first app launch, not at download. (The event-based equivalent used to start a journey is the default event PW_DeviceRegistered.) So a segment or journey built on first install can only contain devices that have already opened the app.

For a notification to be delivered to a newly installed app, the user must open it, for these technical reasons:

1. Registration moment: the first install is recorded only at the moment of the first launch of the application on the device. Downloading the app without launching it registers nothing.
2. Push Token Generation: to deliver a message, the system requires a unique address (push token) for the device. This token is generated and sent to the server only after the application initializes (when it is opened).
3. Permissions: on most platforms (such as iOS and Android 13+), the user must explicitly grant permission to receive notifications. The system prompt to allow notifications can only appear once the app is running.