Sumatra PDF might be a bit more popular than FileApp. We know about 1 link to it since March 2021 and only 1 link to FileApp. We are tracking product recommendations and mentions on various public social media platforms and blogs. They can help you identify which product is more popular and what people think of it.
The names are similar. That is Apple ios Files app you referred to but the one I am looking for (paid for many years ago) is FileApp at https://fileapp.com. Source: over 1 year ago
You can use your browser for both, there are extensions(FireFox - PDF & EPUB/Chrome - PDF& EPUB) for that. In case, you want you use a separate software for them, I suggest SumatraPDF--it handles both PDFs and .EPUB files. Source: over 1 year ago
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