You can download the free Papers app for iPhone/iPad here.

You can select a particular word in the document you are reading and use it to 'search online' from your favourite repositories. You will then be presented with a list of search results of the articles that contain this word which you can choose to import.

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Papers will automatically search your favourite repositories but you can alter these by tapping the search settings tab in the top right corner.

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Papers will automatically search for the selected word under 'all fields' but by tapping on the word, you can change this to search for this word under a specific field.

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