Hi, I've just spotted your job and thought I should bid, as my last project used native-webview... There were a few problems with the release, so the process is still very fresh in my mind. Here's some some guidance on what you will need to consider before committing to a build:
1/ If you want to simply show your website in a webwiew, it works best, for obvious reasons, if your site is optimised for mobile display, so it needs to be responsive, or have a mobile theme associated with it.
2/ Apple tend to reject apps that don't offer any more User Experience than using a website, so you will need to make provisions for adding content to your app in a dynamic way, or at least offer some functions that make use of the device's features (there are various ways to get around this issue).
...I'm relatively new to this site, so I would be happy to provide a physical demo for you, to prove that I know what I'm doing. Just let me know.
I've been in the 'mobile industry' for 8 years and I know what a job should cost, so be wary of quotes over $600, this isn't a particularly difficult project.
I'll leave it there for now, but if you have any questions or would like me to elaborate on any of the above, please don't hesitate to get back in touch.
Best regards
Mark