I'm trying to develop a system where users can add financial symbols to activities, almost as you would tags to a blog post. The user should be able to easily add or remove symbols. They can add as many as they like.
We're dealing with a large amount of symbols here (hundreds of them), so I thought a two list selection ui would work well, with a search bar at the top of the left list. This way users can search for their symbols easily and add them or remove them from the same UI.
This UI is supposed to work on an iPad. Here's a desktop example (forget the up/down buttons):

Several of my team question this interface being used on an iPad, because they've not seen it used on mobile before and they fear it is too complex for mobile.
- Does us implementing this control on iPad when it's not been done before make it a bad UI decision?
- What do you think about using this control, or what alternatives would you suggest, if you don't think it should be used?
