What app for the iPhone 5s can I use that would make the camera better?

I've got an iPhone 5s but the camera isn't really that great and I was just wondering if there was an app that I could use that would make the camera better. (Doesn't have to be free the app) thanks I would appreciate if you could help me.

You can't magically make lenses better. It can't magically become a DLSR 4 inch lens attachment. You can add some stuff to photos though to make them more interesting like effect, filters, borders etc.

What you imagine does not exist.

The best thing that will increase your image quality is you. Your decisions of the lighting will have a dramatic influence on image quality. You need to be conscious of both the quality of the light and the quantity. Quality of light is referring to the direction, whether the light is hard (i.e. Bright sunny day) or soft (overcast day or during sunrise or sunset). The best time to photograph outside is during the golden hours of sunrise and sunset. Because phones use such small sensors, they have small pixels which are notorious for producing images with a lot of noise and for having very low dynamic range. Therefore you need to make sure you photograph under conditions with an ample amount of light AND make sure to use the lowest ISO setting possible. Increasing the ISO is best way to get a ton of ugly noise in your shots. High-ISO images also produce lower contrast, and lower color quality, too. Another thing that improves image quality is composition. Look up the Rule of Thirds and use that as a guide for composing your images. While not a perfect solution, the Rule of Thirds is probably the quickest and easiest way to improve the look of your images. Cameras within phones often cost about $8- that's it! So it's no wonder why it can be so difficult to get good image quality, but it's not impossible as you've seen. Because of the simple design and low-quality of cameras in smartphones *(even the $1,000 iPhone X uses a $25 camera), you have to cognizant of its capabilities and its shortcomings. As I've always said, 80% of what goes into making a great photo happens outside of the camera. Look for great and ample lighting, use the Rule of Thirds as a starting point in your composition, and you'll see a dramatic improvement in your photos regardless what device you're using.