If you have installed Google+ Android App then by default it will upload all the images taken via your phone to your Google+ account.This feature enables you to share your photo from any other device,So you dont need to depend on your phone to upload.
But,this feature also can be pretty annoying because it consumes your Internet Data and you dont have a control over which images to upload.This article will discuss on how to disable Google+ app Auto Upload Images Feature
How to disable ?
Open Google+ Android App and Go to Settings and Disable the option “Instant Uploads”
You can also change the settings so that Photos will be auto uploaded when you are connected with WiFi.Go Instant Upload settings and Select when to upload Photos option and it it to when WiFi is connected.