Enable easy preview of any screen(s) and linking to those screens on Zeplin from within Jira issues.

Illustrator is still a contending tool, is it in the plans?

It's pretty new but promising:

https://affinity.serif.com

Adobe XD support!

Yesterday i wanted to work in an offline situation, but i had to connect my macbook via iPhone to the internet to see the screens i'm working on

There are some transitions that can't be easily explained with prototyping tools. It would be great if there were a way to import a .mov and animated .gif or an animated .png. It could come in as reference and not need any callouts, dimensions or code snippets just display.

Tagging is nice but it's not the solution we need to organise our files. We're having trouble organising multiple pages, page flows and component flows across multiple breakpoints on large scale projects. If we could create folder structures for pages it would make life a whole lot easier.

Provide plugin for Adobe XD, just like sketch plugin,
so that it will be very easy to develop the product.

Add ability to duplicate a project, which means if you want to create a new version of a project you have to start from scratch with content, and members (yes, you have to individually invite every member to the new project, see next point).

Convert SVG assest to VectorDrawables for since Android cant load SVG out of the box. You can load a VectorDrawable out of the box.

see https://developer.android.com/training/material/drawables.html#VectorDrawables
and for converting svg to vectordrawable see http://inloop.github.io/svg2android/

SAML support would help us give a more secure access to devs in a large company

Instead of px measurements generated in the font style CSS, support rem and em measurements.

Ideally with an option to set the html base font-size. (Bootstrap 3 for example sets html's font-size to 10px, which allows 1.6rem to equal 16px, unless someone edits their browser's options to increase font size.)

Can import Photoshop files and generates specs automatically

Similar to the Slack integration suggested, a method with which HipChat can get notified when changes are made. In our HipChat, commits and builds are put into the chat whenever developers make changes. Would be cool to have my design changes being integrated too.

It would be absolutely amazing if you can "export" a document (pdf?) with the details. Like a document for developers.

I wish to be able to export SVG assets for my iOS project type. It's nice to have that I have that capability with web projects, but it becomes more limited for iOS/Android.

Love when my apps have the option to toggle Dark Mode so that my eyes are less strained when I'm working. Would love the same option for Zeplin

Currently, Zeplin doesn't allow a developer to change the name of the file when they are downloading the assets. It is set to auto-override an old asset.

This behavior generally works well, but there should be an option for someone to change the name of the file they are saving.