You can customize the logo presented on the top menu of the Web Admin and to the Buyers as well as in the header of the copy of transactions emailed.
Go to Settings -> Company Profile - > Branding
Upload an image using the recommended size: 458 X 167 pixels and ratio: 1:2.75
In the same area you can also customize the image presented on the Pepperi Home Screen.
Upload a portrait or landscape image using the recommended sizes. See this article for the recommended sizes: How to size our Pepperi homescreen image
Portrait: size for most tablets is 1536x2048
Landscape: size for most tablets is 2048 X 1536 pixels
The appropriate image will automatically display when the tablet is rotated.
The images will be suited to the dimensions of your specific device and you should use the guidelines in this article to determine the dimensions appropriate for the your tablet platform: How to design the Pepperi Home Screen background to support multi-device resolutions