I have a Nexus 5 and a S3 and to say that both camera apps are terrible is an understatement. The N5 currently has a bug with 16:9 zooming and the UI is just awful. On the Samsung I have the google camera just so its the same (both home-screens are the same with the use of the google now launcher as-well). I've been looking at camera FV-5 and I'm not sure if I want to spend $7 on it and the cinema counterpart.I would really appreciate any help and I didn't see photography section so I figured I put it here.
Try Open Camera: https://play.google.com/store/apps/details?id=net.sourceforge.opencamera&hl=en
or Cyanogen Camera : https://play.google.com/store/apps/details?id=com.cyngn.cameranext&hl=en
I have the one plus one and both work great with it
+1 for the cyanogen camera. You must be running on cyanogenmod 11s to get the cyanogen camera from google play. You will need to side load an apk,
Pro Capture has lots of manual options and doesn't use as many resources as Camera FV-5. I have both and end up using Pro Capture more often than Camera FV-5. The Raw capture also really slows things down on FV-5 it's a brilliant app, but out of the two I use Pro Cap more often than not.
Throwing out some love for Focal: https://play.google.com/store/apps/details?id=fr.xplod.focal
Preview images on its page are terrible but its got plenty of manual controls to get anyone up and running with stills. Also adding a +1 FV-5.
I was short of time for the last post, for the quick pic I much prefer Pro Capture but when the photonerd mood strikes me I will run with FV-5. So I guess it all depends what your type of shooting it is you're after, if its for the instagram selfie rubbish picture then you'll want something robust but not power hungry, if you want to fill your stock with nice photos and edit the RAW image than FV-5 is the good way to go.
If you want to get the most out of your N5 try "L-Camera" https://github.com/PkmX/lcamera
It enables you to shoot RAW files that you can edit afterwards. If it's ultimate image quality you're after, this is the way to go. It also enables 120 fps Video if you have rooted your phone.
With nexus 5 i woild use either l-camera or camera fv-5