Did you copyright your own work?
As to others copying it, did you mean the concept or the app?
The concept is by copyright.
The app is a never ending battle of how much you will invest versus others. Most companies lose since you may have thousands trying to crack your protection and you might not have a team for the copy protection.
For me I've sold apps for years to companies. I used a generous license and did OK.
I have created a computer app that I would like to sell. I have 4 books on the subject in which I have found some information about how I can protect my software from copying by others. I'm haven't read every word of all 4 books but what I have read doesn't seem too concerned about avoiding being accused by others of copying their software. How can I avoid being accused of committing copyright infringement myself other that to buy a copy of every program in the same realm and examining it for the same "look and feel"?

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