Technical Limitations for Push notifications

What are mobile push notification character limits?

The limitation depends on your platform type and your screen size.
The approximate values are:

• push description—1000
• push title—200
• text for a button without parameters—20
• text for a button with parameters—1000
• URLs (clicks/image)—2000

The total push size for the latest iOS and Android versions is limited to 4Kb.

How fast are mobile pushes sent?

The total average speed for one project is 1.5 million pushes per hour for both platforms.
If you simultaneously send messages in other channels, this may slow down the sending speed.

What image limitations are there?

For SDK 2.11.0 and later

iOS

• JPG and PNG files are supported
• the recommended file size is up to 5 Mb.

Avoid using long vertical images as the user has to scroll them down to see the bottom part of the image. For example, images with the 2:1 / 16:9 / 4:3 / 1:1 ratios are displayed in full while the ones that have the 1:2 / 9:16 / 2:3 / 5:7 ratios have to be scrolled down.

1:2 ratio image	1:2 ratio image

Android

• JPG, PNG, and WEBP images are supported;
• the recommended file size is up to 5 Mb
• your image is resized automatically depending on your device width.

We recommend using horizontal images such as 2:1 ones so that your image width matches your text width. If you use vertical images, they will be adjusted to the center and appear smaller in width than your text.

4:1 ratio image	2:3 ratio image

For SDK versions before 2.11.0

iOS

• the recommended file size is up to 5 Mb;
• the images are displayed in 1:1 and 3:2 ratios
• the number of pixels is limited to 1038 x 1038.

On iOS your images are resized automatically. If the image size is over 1038 pixels, it is downsized, and the margins are applied to display your image as a square. To avoid this, use the images with up to 1038 pixels in width and less than 1038 pixels in height.

Android

• the recommended file size is up to 5 Mb;
• the aspect size is calculated automatically
• the recommended ratio is 2:1.