When the user tap the pencil icon to edit an image file, there’s a prompt/popup/whatever asking for the user to select which app to use, and a default one can be made. There’s a option for this on DC settings too.
When you tap the pencil icon, it opens the DC editor directly.
Sorry, no .jpg files today Besides, I don’t really mind how you imagine/design/build/implement it.
Sometimes we just want to make that awesome MemeTastic’s meme without getting too far from DC. Keep up your great work!