I am sure they could use an alternative if you ask them (i.e. Skype). I am guessing.
Not when I asked them! It was FaceTime or use the other options to prove your i.d. The other options were not practical propositions for me at the time that I attempted to sign up due to me being out of the UK at the time. In the end I decided that the disadvantages of changing from spread betting to a Swiss CFD account out-weighed the benefits. I seem to recall something about needing to fill out a tax return in Switzerland too but my memory is a little fuzzy on the exact details now.
