So for things like Carrd.co and other single page apps I've used, the SEO is dodgy at best. I think since standard content is hard to do on those types of site

So for things like Carrd.co and other single page apps I've used, the SEO is dodgy at best. I think since standard content is hard to do on those types of sites, your best bet is going to be a lot of backlinks, but even then, it's hard to rank for keywords if your website is structured like a landing page, not a blog. That's just what I would assume though!! Good question!!!