Having to publish in order to be able to test on devices and see any custom code is an unfortunate step in an otherwise almost perfect design/build/test process.
As suggested in another post:
It would be great to have a "preview link" available without needing to publish. Not only could you use it to preview your site on different devices, but you could also share it with others (team members, clients, etc.) to get feedback during the design process as well.
Having to publish to show the site to clients (without them seeing the webflow interface) is troublesome, some amends go through loads of feedback stages before being 'approved' for live by clients.
A 'preview' or 'staging' step would be very welcome feature.