Avatar for Claus Wolf


My name is Claus Wolf and I am delighted you found my little nook on the web.

During the day I am a consultant working with libraries around the world. In my spare time I tend to tinker on the web, write about all things Apple, or create iOS / macOS apps in Swift. If you have questions, please contact me!

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Open Access Helper

iPhone & iPad

There are > 30 million copies of otherwise pay–walled articles, this App helps you access them on your iPhone and/or iPad!
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Open Access Helper


Combine the power of unpaywall.org, core.ac.uk, opencitations.net and more, all in one convenient Safari App Extension!
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Open Access Helper

Chrome, Chromium & Firefox

Other might port their Chrome extension to Safari, I ported my Safari App Extension to Chrome & Firefox!
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Den Spesensatz für deinen aktuellen Ort immer und überall, schnell zur Hand. Inklusive Wechselkursen - ideal für Geschäftsreisende.
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Sesam2050 bietet inzwischen > 23.000 ausgewählte Datensätze zur Fachliteratur der Kinder- und Jugendliteratur mit deutschsprachigen Metadaten.