[dspillett]

> > Web pages that don't show anything without JS are broken.

> What about web applications?

I would say is depends upon the application.

A data entry and simple reporting service? That should definitely be accessible and can easily be made to work without JS. Though some scripting might be acceptable: modern screen readers will cope and holding back for people with ancient screen readers is no different to holding back because some people still use IE or Android 4.4 (though do some research/testing to see what they actually w{ill|on't} commonly cope with).

If it is an interactive game or similar then you are not going to replace that practically with form submissions and no JS, so by all means don't bother caring that it doesn't work without JS. Though do make sure you include a <noscript> tag if otherwise nothing useful would display, just so users know what is going on and there isn't a fault at their end or a fault in your app that they should report.

Anything between is a grey area: you'll have to use your best judgement of your actual and potential target audiences. Though again, make sure something useful displays for everyone even if that is just a polite "sorry, we can't get this working for you" message.