I've found using a digital camera I have to set the image size to the lowest, VGA 640x480, and then crop the photo as small as possible. Even then I sometimes can't get the image under the 125kb required and it might take several goes to get it right which is really annoying. I've also found I need to use the old Windows Photo Gallery to tell me if it's under 125kb. I'm not sure but on a phone camera you might not have the capability to do this.