Accessing API from EPoS System

I’m needing to complete an integration between an EPoS System and a Shopify website (specifically the GiftCard parts) using the APIs.

The EPoS is not web based and there may be multiple tills in multiple branches needing to use it.

We may in future have other customers needing to use the integration.

Which distribution (and authorization) method do you think I would need to use?

https://shopify.dev/apps/distribution

Any advice much appreciated.

This is a pretty personal choice based on what you intend to do with the app and the audience. If you think there’s a big enough audience it’s likely worth making it a public app to make it easier for others to find and install. It will have some approval steps the other 2 types don’t have so maybe that might impact your decision making. Whether you want to use the billing api or not will help force you in a certain direction. If it’s more likely to be a one off and the build will be done as a billed project you might go for the single merchant install link.