I am developing Point of Sales (POS) for Windows. I am torn into two choices, to develop it as desktop app or modern app.
From my understanding, WIndows Store does not publish desktop app directly. I want to sell my app in Windows Store, so that leaves me with modern app.
However, I also understand that Modern app is not meant for complicated application. The POS shall contains inventory, user and shift management, supplier info and some business intelligence and might get complicated in the future. Can Modern app cater this?
Also, what is the limitation of the Modern app? I know that I would need to follow some design convention by Microsoft, but other than that will it be sluggish when the data is large?
For your information, I am using SQLite as the standalone database.
I think You should consider first your revenue model. Maybe there you'll find some insights that will help you decide.
However, I think goin the mid path can led you to a better environment.
I will consider you are not only developing an app and uploading it to a website and expect people to fall from the moon into your website, and pay you and download it. I will assueme you have a sales team, a quality of service and so on.
Considering all windows os support winforms applications, developing a winforms client is a must and safe bet (again, the revenue of the bet depends on your sales force). But you also need to design an application architecture. I suggest you to develop a backend (that will deal with inventrys, historic archives, business rules, etc) you can install on your customers infrastructure, or (guess what?) offer it as a service.
Over that backend, according to what your customers infrastructure is, you can offer web clients, desktop clients or Windows store clients. Each with their own cons and pros you can use to your own benefit without disregarding your customer goals.
Besides that, Try to offer something good, easy and fun. POS systems always are so bored that there you may have an opportunity to differentiate.
You are also worried about the performance of the apps. Well, most of it depend on the backend and its infrastructure. I think your still thinking on a fully local application, but you can design a better architecture, open you business opportunities and deliver a great experience by knowing better practices and more modern architectures.
The biggest difference you need to consider is that Modern Apps run on more restricted environment than desktop ones. Accessing hardware components and system resources is more limited and, depending on what your app does, that can be an issue or at least a headache. With desktop, you still have all access as we are used to from windows 95, but there is also more security issues. Windows store apps also are more difficult to be pirated.
Hope this helps and gives you a better understanding on what to do next.