However, Retool is more primarily focused on internal tools. Most things built in Retool are employee-facing rather than customer-facing. For example, a typical Retool use case would be an admin panel dashboard that lets your customer success team lookup and edit user data.
Retool does support externally-facing apps as well, but it's not their primary focus as a company.
Depending on what you're trying to build, one or the other might be the right fit. Both have free versions that you can sign up for online and try, so you may just want to sign up for both and try them out.