The WholeSlide iPad app was developed to enable rapid access and rich interaction with large (1 gigapixel + ) wholeslide images hosted online. The app allows users to natively zoom into a wealth of image types: from neuroanatomy and developmental biology to pathology and histology resources. It’s available free on the iTunes app store.

Figure 1. Main Menu, Set Browser, and Tile Chooser.

Basic usage

Select a site from the main menu to show a list of available data sets. Selecting a dataset will present the list of wholeslide images for that set available to view. Sites and sets are organized based on their own internal structure. Some sites are grouped by folder while others are searchable. Selecting an image will load it into the viewer.


The WholeSlide App provides tools to interact with wholeslide images on the iPad. Individual tools are toggled on and off using the buttons located immediately to the right of the Tile chooser. Tools can be dragged around the screen using their top handle.

Image Metadata

Here you will find pertinent slide data, including species, stain, native resolution, and attribution. We are limited by the information made available via each independent site and are working to increase the depth and breadth of this content.

Image Adjustment

Here you will find controls to adjust the bright, contrast, and RGB windows of the image. Thanks to the processing power of the iPad, we are able to perform these adjustments in real-time on the device itself. The RGB windows allow you to scale the relatively red, green, and blue channels, but the easiest way to understand how the RGB windows function is to try them yourself.


Here you will find a thumbnail of the current image, the effective magnification in screen pixels, and a slider pad to quickly move between images within a dataset

Adding/Remove data

The WholeSlide application contains links to over 70 Terabytes of image data from the start. However, many researchers and clinicians have their data on University-run image servers. Users can add custom sites and data sets within the app itself. We currently support Zoomify-compatible single tiles and sites that provide an RSS feed of the available tiles.