To preview the app in whole, including the menu and app styling choices, an iOS device is necessary. However, if you are working with a designer that does not have an iOS device, there are a couple ways they can still help you:
1. He or she can design your article template by previewing it in their local browser. They can check how the article template responds to the various viewport sizes by using a plugin like Window Resizer, available free for Google Chrome.
2. If he or she has a Mac, they can download Xcode from the Mac App Store. One of the tools that comes with Xcode is the iOS Simulator. Your designer can preview the article template inside iOS Simulator and check the design against various iOS devices within that tool.
You may first want to send your designer the content of a couple example articles, and have he or she design the template around that content. Then when the design is good, have him strip out the sample content and insert the template tags found in our documentation.