# Mobile Push Overview

#### Mobile Push – Direct User Communication

Push notifications are short messages sent directly to the devices of users who have installed your app. As one of the most effective engagement channels, they allow you to share updates and promotions even when the application is running in the background.

### MessageFlow Features

Our panel and API support the complete push notification management process. Depending on your sending method (API or Campaigns in Panel), we offer:

* **Sending & Personalization**: Full content configuration and message personalization tailored to user needs – available for both bulk campaigns and transactional API sends.
* **Segmentation (Campaigns)**: Audience base management within the panel.
  * *Standard:* Built-in static segmentation (creating groups based on uploaded lists).
  * *Add-on:* Advanced dynamic segmentation available within the MessageFlow Segments add-on.
* **Targeting**: Precise notification delivery to defined groups, significantly increasing campaign efficiency.
* **Monitoring**: Real-time tracking of delivery status.

### How it works?

To make sending possible, the mobile app must establish a connection with a dedicated notification server:

* iOS: Apple Push Notification Service (APNs).
* Android: Firebase Cloud Messaging (FCM).

During the registration process, a unique token is generated that uniquely identifies the device and acts as the key for delivering the message.

{% hint style="danger" %}
**Important**: The user must consent to receive notifications (in compliance with regulations).
{% endhint %}

### Technical Specification

To ensure your notifications are effective and display correctly, follow the guidelines below.

**Character Limits – Title**

* iOS: max. 35 characters.
* Android: max. 46 characters.

**Character Limits – Content**

* Collapsed view (before expansion): max. 171 characters (place the most important information at the beginning).

{% hint style="success" %}
***Pro Tip**: The shorter the notification, the more engaging it is.*
{% endhint %}

* Expanded view (text only):
  * iOS: max. 250 characters.
  * Android: max. 450 characters.
* Expanded view (with image):
  * iOS: max. 250 characters.
  * Android: max. 101 characters.

**Image Requirements (Rich Push)**: Allowed formats are .jpg, .png, .jpeg, and .gif.

{% hint style="warning" %}
**Note**: GIF animations display correctly only on iOS devices.
{% endhint %}

* File size: Maximum 500 KB (recommended for both iOS and Android).
* Dimensions:
  * Minimal: 512×256 px.
  * Optimal: 1024×512 px (2:1 aspect ratio).
  * Maximal: 2048×1024 px.