post a photo

I use various different methods, depending on where the photo is stored.

Sometimes I just find a pic (e.g. a recipe) online, and copy and paste it into my post, by right clicking the image, selecting copy, placing the mouse/cursor back in the right place in my forum reply, and then pasting.
Sometimes I use a photo I have saved to postimage.com and use the link that postimage supplies for forums. That is also a simple cut and paste.
Other times I have the pic saved to my computer, and use the Upload a File button below the post.

These things seem to work on all the devices I use (phone tablet and laptop), but I very rarely use the Image button on the top of the Reply box, since that just asks for a URL

I use imgur to host my pix for posting in forums, I also hot link to pix on other websites such as Google...