Recently a new store emailed me about how fake reviews work in Google.
Just to make sure, the star will appear even if it not real reviews ? I mean I can put fake reviews on my website as I launched it few weeks ago so I do not have much review.
Neither your reviews app nor JSON-LD for SEO will stop you from adding fake reviews but I'd strongly discourage it.
Fake reviews are a violation of Google's guidelines and if you're caught doing it you can potentially lose all of your Rich Results, have your pages removed from the search results, or even be banned from Google completely.
I've also heard it's against Shopify's Terms of Service so you could have your store closed by them too.
I strongly, strongly discourage using fake reviews. It's better in the long-term to have no reviews and gather them normally from actual customers.
One SEO feature that actually works is structured data.
Mostly because the data helps Google's algorithm which makes their job easier.
You can either audit, code, and test your store's structured data by hand or install JSON-LD for SEO and have the structured data you need for several types of Rich Results.
It's already helped a few thousand Shopify stores with their structured data and it could help you too.