This depends upon the potential degree of involvement and recognition of the University of Birmingham.
If your app has been developed as part of a project which forms part of your studies, the degree of University involvement to be acknowledged is a matter for your College.
There is a basic principle that inventions, discoveries, etc (where it is considered that there may be a commercial significance) made during the course of a registered students studies or the normal duties of a member of staff give rise to intellectual property (IP) rights are in favour of the University.
To assess whether or not your app qualifies as an Invention that may be of commercial significance you are advised to discuss this with your College Director of Research and Knowledge Transfer and Alta Innovations Ltd which has responsibility for commercial exploitations for the University. For further information about this please contact Catherine Mansall in the Enterprise Development Team.
The University Regulations explains in more detail Patents and the Exploitation of Inventions (section 3.16) and Intellectual Property (section 5.4) and can be accessed at www.birmingham.ac.uk/Documents/university/legal/regulations.pdf
For more information please contact email@example.com