You have to upload the picture to a website (which you can watch from @isteemithard or @ilyastarar post). And, when you get the link from that website, I don't think there will be a issue to uploading it from a mobile.
Secondly, whales attention is not easy to grab, I am working on that, therefore follow me and I will update a blog soon regarding that.
Lastly, every website work differently on mobile and desktop... I prefer to use it on a laptop/desktop.
Cheers!