This is a growing issue with most smart devices. We're dealing with a smart phone that wants to be a camera, but just doesn't have the capabilities of a full sized camera. A camera app will not support an inferior camera on a device which wasn't meant to handled the larger picture sort of speak. However if you feel that you really want to explore this side of the devices.. an App called Open Camera has many customizations which can help you better the images taken with your smart phone. As I said,, the manufacture has limits on what lenses etc can be installed on your devices..
We live in a world where cameras want to be smart phones and smart phone want to be cameras.. and I've yet to see a successful merger of the two. lastly, always remember that the lens takes the pictures not the device. so if the lenses are inferior, you'll always have a poor quality photo.
For instance: I took this picture this morning using my smart phone:
Note the grainy appearance.. reasoning.. is that my smart phone hates low or yellow tinted light.. On the other hand, look at this image taken last year while at a car show in bright light: