Why is Piktures not open-source?

The code is all we have
We have worked 6 years on developing Piktures and there are many concepts which are unique to Piktures.
The source code is our intellectual property and it is where the value of our work is stored. We don’t have a database of users, we don’t have a service with a social graph, we just have a fantastic app.
Making Piktures open-source would let other developers steal our intellectual property. We have come to believe that the Google PlayStore is filled with other gallery apps that have copied the original gallery app from Google. While we are not sure and cannot prove this, it is quite striking that they all look the same.
Their mission is to generate revenue easily by filling those gallery apps with ads without taking the time to create an original gallery app.
We are different, we have created something unique and we care deeply about it.