Manipulating a spreadsheet via touch in Excel 2013 is a decent experience, takes a little practice to figure out the behavior, for instance if you want to resize a cell you first tap on a cell boarder that activates a resizing arrow and then do the resize, rather than grab the cell boarder directly and then moving it like it would work with a mouse. Manipulating scripting on the other hand doesn't offer any touch optimizations, it's the same desktop UI that's always been there. It's possible to do it but definitely not a touch UI. A device with a digital pen can help out a lot with working with a desktop UI in these kinds of situations. It's not going to replace a keyboard and mouse for speed but it's definitely possible to do quick stuff debugging code and make small edits and changes.