Should app be fully integrated with Shopify?

I've read this article https://www.indiehackers.com/post/shopify-app-store-an-underutilized-acquisition-channel-853ba030fe and initially had the misconception that it would be okay to take an app that provides utility for Shopify and offer it within the Shopify App Store.

I possess an iOS and Android application, which, in my perspective, could offer value to Shopify users. Does it necessarily have to be a fully integrated, Shopify-centric solution?