I've had difficulty for years trying to get a decent pair of gloves that aren't too bulky, keep my hands warm and allow me to use my fingers for my phone & mp3 player without dropping everything due to bulk and lack of movement. Plus I have very narrow hands, long fingers but I'm very slim so not a lot of XS sizes in good makes.
I purchased a pair of Mountain Equipment gloves which have silicone pads on the hands and fingers, which along with using crutches, turns out they were very comfortable, allowed a great deal of movement but weren't overly warm.
Poor blood circulation has always been a bit of a problem for me so I purchased a pair of ski gloves and although they kept my hands very warm and snug - very comfy also - as you'd expect from ski gloves there wasn't a great range in movement or flexibility for me.
Having visited an outdoor store, it was recommended to me to purchase a pair of liner gloves in merino wool. They would keep me well insulated due to being merino wool, I'd have all the flexibility I required and with being a liner glove I could wear them underneath my fleece Mountain Equipment gloves. Although they're a S in size and just a little bit big for me (don't think Icebreaker has XS gloves, couldn't locate any anyway), underneath my other gloves it's heaven! I've got full range of movement, flexibility, excellent grip for my crutches and better than anything they keep my fingers lovely and toasty.
In conclusion I would highly recommend these liner gloves, you won't be disappointed!