Alias, or the URL part is a vital detail of a Smart Page. On Shorby, you can transform your generic short URLs like shor.by/X4t2N9 to something good-looking like shor.by/leather-wallets and use that link all over the web.
The number of editable alias for Smart Pages depends on the subscription plan you have. The Custom Slashtags part is the one related to alias.
Rocket Plan - 10 links with custom slashtags;
Pro Plan - 50 links with custom slashtags;
Agency Plan - 250 links with custom slashtags.
If you are a Pro/Agency account holder, setting up custom domain will appear in this part of Settings&Style. Click here to find out more about custom domains.