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Note that currently, if you would like to reference an image in your README.md, you'll need to use an absolute URL to wherever the image is hosted. You'll also need to ensure that the image URL is always accessible.  We recommend that if you are hosting your own App repository, you images you need there. This will ensure that if users can download your App to install it, IGB can also download the image. 

Also see Share your App - the IGB App Store

Example README.md for an IGB App

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