I want know how to get the new photo filters in the camera on my iPhone 4 I want to know how to get the new photo filters in the camera on my iPhone 4 because my friend has them on her iPhone 4s. How do I get them?
I think the filters you are talking about were added with iOS 8, the recent iPhone operating system update. Unfortunately that update won't install on your iPhone 4.

There are a number of applications available in the App Store that provide similar photo filters though.