Copyright protects the expression of an idea rather than the idea itself. So, if your friend scoops an idea you have for an app, it is unethical but not copyright infringement.
In Canada, copyright lasts for the life of the creator +70 years.
Thereafter, copyright expires and the work enters the public domain. Works in the public domain can be used freely without payment or permission from the copyright owner.
The copyright symbol © we are accustomed to seeing is optional. It is a visual reminder that a work is protected by copyright. All online works are protected by copyright, unless there is a notice stating otherwise.
Copyright owners can register their copyright with the Canadian Intellectual Property Office. This serves as proof of ownership should any questions arise.
Copyright infringement occurs when a person does something with a copyright-protected work that only the copyright owner is entitled to do, and does so without the copyright owner's permission.
A local independent video game developer related the following unfortunate situation:
At a convention, he joked with employees from a large video game company that he should develop a Korean boy band (K-Pop) video game. They loved the idea and invited him to pitch it formally.
The company ultimately declined his pitch ...but released a nearly identical K-Pop game months later. Because the local video game developer did not ask the company to sign a non-disclosure agreement (NDA) prior to the pitch, he had no grounds for legal action :/
Please note that the information provided on this site is for educational purposes and is not intended as legal advice.