[Android] Allow opening item attachments (PDF/HTML/EPUB) in external app

cheflo · January 29, 2026

The built in viewer/editor for attachments is great but sometimes it is useful to be able to open attachments in an external app, just as is possible on the desktop version of Zotero. While this has utility on Android devices, it is particularly useful for e-ink devices (such as supernote and boox). The general Zotero Android interface already works pretty well on e-ink screen and taking advantage of the built-in apps' reading and annotation capabilities would make Zotero on e-ink a great experience.

I don't think Zotero needs to do anything smart with the annotations taken in the external app. A long term goal could be to extract/copy them automatically to Zotero annotations, but it also seems fine to leave it up to the user to perform this step on the desktop when/if they desire to.

Edit: I broke the pagination suggestion out into its own thread here https://forums.zotero.org/discussion/129541/android-ios-add-pagination-page-turn-navigation-to-html-snapshots?new=1

ivnsp29 · February 6, 2026

Edit: My initial comment was a +1 on the request to the developers, however after reading more into it I realized it will probably not happen anyway.

To the OP - check the answer on the same request before https://forums.zotero.org/discussion/comment/476294/#Comment_476294

I guess what is left for the unsatisfied zotero for android user is to request improvements in the android app (as much as I enjoy using the internal reader on the desktop, the experience on android and especially for eink devices is somewhat disappointing).

cheflo · February 18, 2026

Just saw you edit now @ivnsp29. It seems to me like an option to "open in external app" is a smaller ask than improvements to the default reader to the point where it become a viable alternative in all use case. Particularly on e-ink devices, where the apps tend to be somewhat specialized and it might not be a direction where the Zotero devs want to spend a significant amount of resources. It also seems in line with the design philosophy of the desktop app, which retains this option even after the introduction of the excellent PDF reader within Zotero desktop.

adamsmith · February 18, 2026

To be clear _opening_ in another app isn't the challenge. It's open in another app and then have a reliable way to get the file saved back to Zotero that preserves the annotations, integrates them into Zotero appropriately and doesn't cause too many sync issues.

That's mostly the case with local file storage on Desktop (which is why that allows for external readers), but it's a good bit more complicated with mobile apps and Zotero devs have been quite clear on multiple occasions that it's not something they're planning on doing.

cheflo · February 26, 2026

Thanks for the reply! I understand that it would be a challenge to preserve annotations made in an external app in Zotero. That's why I was suggesting to only allow the opening in another app. As long as Zotero could consistently open the same file in an external app that would be valuable, particularly for e-ink devices which have built-in readers optimized for e-ink in a way it seems unlikely that the Zotero android app would become optimized.

But I hear what you are saying about this not being a priority by the dev team so understand that this is not likely to happen and I will think of other ways to use my zotero library on an e-ink device.

zaiyajin · 2026-10-26T11:35:16+00:00

I've just discovered the beta version of Zotero for Android has a built-in viewer for HTML and epub files. This is a much welcome new feature, but I'm bummed to find out that Zotero now totally prevents us from opening the attachment with an external app.

I foresee working directly with the built-in viewer for annotations and such, but I do also foresee using external apps where appropriate. For example, KOReader's annotations can be imported to Zotero fairly easily, so some may want to keep using it for reading. Or may be using an external app for text-to-speech.

I'm all for better built-in viewers, but I don't see the point of preventing the users from sharing/exporting the attachment. Some attachments are not expected to be viewed by the built-in reader, in which case we would open with an external app. Why should we not have an option to do the same and let us open it with both built-in and external app, based on the user's work flow?