Sell app to Merchants On The Shopify Marketplace and also allow free use for some?

[ahmedkhan1]

Hi,
I'm developing an app to sell to merchants on the Shopify store. This app will integrate features I previously paid for using other apps on my own Shopify store. Now that I've built my own app, can I list it for sale on the Shopify store and also use it for free on my store and my brothers' stores? If so can you tell me how?

Thanks