I'm researching the question of how to best collect data from people on how much they slept.
Rather than requesting a text / integer value, I want to investigate the possibility that putting in the user's start and end sleep times might yield better results. This would remove the need for users to try to work out the total.
With this in mind, are there any good examples of touch based inputs that would get the beginning and end times easily? So far the best I can think of is a slider with two handles, but the interaction is a little fiddly on smaller screens.