Proxy on android?
The title says it all. This is a single missing feature on android (for me). Otherwise the app works very well. To the point I bought a tablet to use it for research. The syncing of scribbles over pdfs is fantastic (the tablet has pen input and it works out of the box! )
That obviously wouldn't work in Zotero (desktop or mobile), since it doesn't have access to those in-browser proxy settings.
But you want the ability to enter a proxy configuration in the app that's used only for PDF downloads, not for Zotero syncing or other HTTP requests?
We can think about that, but it's a pretty rare use case. The traditional way to do this is a proxy auto-config file, which tells HTTP clients which domains should connect via the proxy and which shouldn't, and that's generally something an institution just provides, since the institution has the canonical list of what sites it can proxy. But you could in theory create your own PAC file with the domains you use most and configure it in your system proxy settings. Zotero would then use it.
In the future, we'll be looking into creating a proper Zotero Connector on Android — at least for the browsers where we can, like Firefox — and that could allow it to take advantage of in-browser proxy settings. That would include web-based proxies, which currently don't work with the Android app either because Android, unlike iOS, only makes the URL available (rather than the document/cookies) when sharing a page to the app.