I like Google Photos, as it continuously syncs the photos and videos on your phone to an online account. Shortly after taking pictures you open a webpage on your computer and can download the images from there without having to email them. It should auto-rotate images, but in the case that it doesn't there are editing tools built-in.
Also plugging your phone into your computer would let you select files directly off the device. The image should have a rotation flag set in the file itself that the forum software will understand.