Android banner (push image) requirements

There is no single required resolution or aspect ratio, because Android devices vary widely; Android scales and crops the image as needed.

Basic recommendations

• File size: keep it at or below about 1 MB so the image downloads quickly and does not add load when the push fans out.
• Resolution: almost any resolution works; around 1000×1000 px looks fine. Above 2000×2000 px is not recommended because of the file size.
• Formats: JPG / JPEG, PNG and GIF. Note that animated GIFs are often rendered as a static frame in the Android notification tray — whether the animation plays is up to the device and its launcher, not Pushwoosh.
• Aspect ratio: nearly any ratio is technically supported. 2:1 is recommended; 16:9 and square are also common. Prefer a center-cropped image, since Android center-crops the banner.
• Hosting: the image must be reachable at a public direct URL that Pushwoosh servers can fetch.

Things to keep in mind

Banner behaviour is entirely controlled by Android and by the device's notification UI. The Pushwoosh SDK passes the image to the operating system, so inconsistencies can appear on devices with custom skins (One UI, MIUI and similar).

For the expanded banner to be shown in full, the message should be the topmost one in the notification shade; otherwise parts of it (header or content) may be cropped.