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In my opinion, you'll need to work on both. But I'd start with whomever has the highest amount of domain authority and/or traffic first. But the most likely case is that people will find out about your B2B app from the Shopify / Bigcommerce / 3dcart sites. The fact that your app is listed there creates a lot of trust and confidence, and is likely the first place that people who have that type of shopping cart system will start to look. I'd make sure that you upload as many screenshots, content, etc, and try to get great rating on these sites first. Your corporate site, though, is the place that people who really want to know more about your company, before they purchase the app, will then go. Your corporate site, though, is less likely to have as a high a domain authority... but you can help reinforce the app listed on the shopify / big commerce / 3d cart sites with strong content and links directly to those pages. I hope this helps! -- Jeff