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I use the the stock camera app. I like camera+ better as a camera but I can't set it to the default camera so I rarely use it.
 
Normal camera. I only use it from the lock screen now, do not even use the home screen icon.
 
Camera+

I really like Camera+ and have it on my home screen as my primary. Also, since I'm jailbroken, I have Activator set so that I can double tap the lock screen clock to jump straight into Camera+ which is awesome.

If I ever need to record a video really fast I use the regular camera shortcut from the lock screen to do that.
 
Normal (iOS) camera if it'll do, especially now that it's on the lock screen.

Otherwise ProCamera if I need the features (I like the 720p video).

Or, NightCap if I need the long (up to 1s) exposure time.

Never Instagram. I have other post-processing apps, and I don't need the sharing aspect.

Regards,
Tom
 
I would use Camera+ if it could be made the default App from lock.

Otherwise the standard App
 
As everyone else said, I take pictures using the stock app, but then filter them through instagram.
 
I use a few different ones for different purposes. Usually it is easiest to use the standard camera app... but I also use some of the following:

Camera + pro
Pro HDR
TiltshiftGen
GIF SHOP
Photo Synth
Toy Camera (not as much anymore)
Photogene
 
I always use the regular camera app, then will import to instagram or other app. Just force of habit I suppose.
 
Camera Awesome is free, filter effects are not. It is a really good camera app. Touch the screen with two fingers at the same time to open the focus box and the exposure circle. Made by those at SmugMug.
 
I use the stock camera more often than not (which I then take the images into Camera +, Instagram, or some other program for filters/ effects), will occasionally snap straight from Camera+, and, if it's dark or poorly lit, I'll use NightCap for some amazing low-light pictures.
 
I use the stock camera app if I'm taking something from the lock screen, but if the phone is unlocked, it's Camera+. I find it to be far superior to Apple's camera app.
 
ProCamera for general use. It has long had all the features that Camera+ only just got recently, plus ProCamera has most of those same features for video recording as well.

NightCap for low-light and long exposure.

PhotoSynth for panoramas.

Pro HDR for high dynamic range.

i3DSteroid for 3D stereoscopic and/or anaglyph.
 
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