The Lollipop camera app (which, if it's not already available in Play, will be shortly) gives you better control over cameras that allow that control (shutter speed, lens opening, etc.) It doesn't make the camera any different.
However, 98% of how good a picture is, is the ability of the photographer. If you take a picture in such a position that your camera is metering a spotlight, don't wonder why the rest of the picture is shades of black - you were telling it to get a good exposure of the spotlight. Learning your camera goes a lot further toward a good picture than more megapixels or a better app. (Ansel Adams, probably one of the best photographers ever, used a wooden box camera. Dorothea Lange (she was famous for her Depression-era pictures of poor people) used a Brownie many times. (That was the 0.5mp camera of today - you gave it as a gift to a 5 year old as his first camera. Look at some of her work on line - it's WHAT she took, and the lighting, not the technical qualities of the pictures, that make them so great. You can actually feel the hopelessness.)
ANY current camera has the ability to take great pictures. The stock Jellybean camera app has the ability. I have the ability to take pretty decent pictures, but I'll never be a great photographer (I don't have the eye for it), even if I used a $4,000 Hasselblad. I'd get the same pictures I get from my 3MP Fuji.
Read all of Kodak's online literature about how to take pictures - it applies no matter wht the camera is. Rule of thirds. Perspective. Selective lighting. Depth of field. Those are photographic things, not camera things. Get good at those and you'll take great shots with an old box camera you buy for 25 cents at a yard sale. You don't need more than 10MP to make something you can print at 8X10, but if you want to approximate 35mm film you need about 1GP, which isn't going to happen soon.