Hello!
I am an experienced Blackberry 10 developer, I've been doing it since the introduction of the new system a few years ago. Many of my applications have Built for Blackberry mark, it is given to the apps deeply integrated with the system, highly optimized and user friendly. I have the experience in porting android apps to BB 10 too. Check out my profile and my website: [login to view URL]
If you want examples of my apps, just message me I will provide you with apps and games I made and are actually in the Blackberry World store.