Is it possible to buy without enering email adress?

Hi,

There is no option for that.

Hi,

The whole system is based on the email address. So it will be complex to add. On top of that, so far we didn't had much requests for that so it wasn't planned.
I don't see us adding that soon.

Hi,

What you could do is deactivate the telephone field in the Display>Custom fields menu, rename the email field to "phone number" (or whatever) with a translation override ( www.hikashop.com/download/languages.html#modify ), and then have a small plugin adding the @domain.com to the email field (either with some javascript code on the checkout, or in the POST with the onAfterRoute trigger in a system plugin).
So that's indeed possible but it requires a bit of coding.

No, I mean you could create a plugin of the group "system" and implement the "onAfterRoute" trigger of Joomla to add the @domain.com after the phone number.
This will require PHP coding skills. It's not difficult if you're a PHP developer but if you're not a developer it will be impossible I'm afraid and you'll have to ask a developer to work on that for you.
That's something we could potentially develop for you if you're interested. In that case, you can use our contact form to request a quote on such job:
www.hikashop.com/support/contact-us.html

Regarding the addition of a placeholder for the email field, you can edit the file "sub_block_login_registration.php" via the menu Display>Views and add it to the input of the email there.
If you know HTML, it shouldn't be a problem for you to find the input in there to add the placeholder attribute.