Hi Janet, I work with libraries primarily in Jordan. Here are a few sites where I have found free Arabic books.
http://www.rampjo.org/ar/%D8%A8%D8%B1%D9%86%D8%A7%D9%85%D8%AC-%D8%A7%D9%84%D9%85%D9%83%D8%AA%D8%A8%D8%A7%D8%AA-%D8%A7%D9%84%D9%85%D8%AC%D8%AA%D9%85%D8%B9%D9%8A%D8%A9 - Free PDF books. There's not an app that I know of.
https://digitallibrary.io/ar/ - Global Digital Library - You can set up a free account and then choose your language. There doesn't seem to be a way to download, but perhaps if you contact them, they will work with you.
Room to Read, at literacycloud.org used to have some good books but when I checked today, there were no Arabic books listed. They say they are redoing their website and that previous content isn't there but that they will be adding more. I'm hoping for more Arabic.
I'm always on the lookout for more open access Arabic books to use with children in under-resourced communities, so I'll be curious to see what other responses you get.
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Libby Bergstrom
Project Director
Global Reach Libraries - IDEAS
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