You don't even own the freaking phone yet and you're already wanting to replace the stock camera app? Here's an idea. Why don't you TRY it before you complain about the stock app. The RM3 actually takes pretty great pics already with the stock app. Some people...SMH.
If I'm spending £300-600 it is perfectly reasonable to want the best software, especially when the nubia has a rubbish camera set up and seemingly no updates either