Remove Image GPS Info
A picture taken with a smart phone can contain lots of embedded metadata - including GPS co-ordinates, or location information.
If you are concerned about privacy, it is a good idea to remove the location information before publicly sharing an image.
In Yosemite, using the Preview application:
Metadata is not supported in JPEG 2000, PNG, or GIF, so, converting the image to one of these formats will remove any location info. In Preview, File > Export, select Format: PNG.
Metapho ($2) can view/edit EXIF data directly on your iPhone.
ImageOptim is an excellent (and free) application that makes images take up less disk space and load faster, without sacrificing quality. It optimizes compression parameters, removes junk metadata and unnecessary color profiles. It will also remove location info when Strip JPEG metadata is checked in the Preferences. Use it to strip metadata and optimize images before sharing: