I'm not quite sure I understand your question on how to transfer a domain to another. Would you mind clarifying that for me? In terms of removing the domain, if it is a Shopify purchased domain, then we can help remove the domain through our backend tools. However; if it is a third-party domain, you should see a trash icon to delete the domain when viewing the domain in Online Store/Domains. As for Google, it can take Google up to 90 days to crawl your store for new information, so if you recently changed the domain, then this would explain why your older domain is appearing. You'll want to resubmit your sitemap to help update this faster. I'm also not sure I understand your question about apps. Could you clarify that for me as well?