I don't think you're understanding the fundamentals here...
A NATIVE app for iOS must be written in Objective C or Swift.
A NATIVE app for Android must be written in Java.
You simply cannot compile and deploy a web application written in Django to Objective C or Java (to the best of my knowledge).
However, it's possible to write an HTML5/JavaScript web application that can be compiled to one of the respective native platforms, using Appcellerator or PhoneGap. The backend data provider for such an app could certainly be a REST API powered by Django.
I don't know Objective C or Java, so I stick with the tool set I know - Django, Python, HTML5, Twitter Bootstrap and JavaScript to create mobile friendly web apps. These are web sites using responsive CSS to format the content best for mobile and tablet viewports, but they are NOT native iOS or Android applications.