I've identified a distinct issue with mobile phones and tablets uploading.
One of the most basic actions in Webbrowsers has been the ability to upload pictures and files however with 'mobile' devices it seems to be a bit more of a problem. On older mobile phones it wasn't a problem. I think it's mostly an issue of security and privacy. Probably national security rather than personal but thats not really relevant.
Opera mini might be an option for direct uploading (still not had a successful upload, tested dolphin, chrome , androids built in browser opera 12)
For gmail theres a few programs for adding attachments to emails but ... still rather annoying.
There are a few options to work round these issues The easiest is to use a site like facebook or googles picassa or twitter which have apps to allow you to upload to your page feed or options such as dropbox or google drive, (which are essentially online storage).
You can then post the url of the image to do the file upload. Another niggle when gardeners world detects a mobile browser it gives a basic text box for editing (so no pictures) you can get round this by using request desktop site in your browser settings.
So you can upload pictures from a mobile by this process.
take picture with mobile/tablet , share to facebook or other 'cloud' site with an app for your device. Use the images url to add the photo to your post.
The alternative to this would be for a dedicated Gardeners World app so you could share directly to the site in some way. Thats not a minor thing to develop. Especially as you need 3 versions to be developed and maintained
Of course you can transfer photo's to your computer and do things that way.
It could be great fun in the warmer months to be able to take photo's at the gardening shows and upload them on the day.
Would there be much interest in a gardeners world App?