I have a patent which describes a system and its functions; I have realized said system by creating a physical device, making an embedded system for it, and it is now commercialized.
Due to the very specific nature of the device, the parts used are very expensive, therefore the device itself is expensive and margins are rather low, although this is no big deal since it's not my main source of income.
Recently, an App came to my attention which realizes the same functionality described in my patent, albeit using smartphone/tablet hardware instead of a dedicated device.
Such App is both available for free, and as with most apps, in a "Professional" paid version.
It also exist on the market an accessory, made by a different company, that once matched with this app renders the phone/tablet and my device functionally the same.
I am already seeking legal advice (haven't found the right lawyer yet), but in the meantime I am curious if I can hope to get something out of the situation: is it realistic that a judge would rule anything in my favor, like the developer needs my permission, or royalties get involved, or anything else?
This question is not about the software and the copyright of the source code; I am based in the EU.
P.S. I just learned that Patents StackExchange exist, please advise if this question should be migrated there.