Mouse over

[vincentqb]

When reading XKCD, there is a "mouse over text", or a "alternative text" adding to the image. There is no way of reading it. How about long press on the image?

[David-Development]

Yes, probably this is possible. I don't want to use external libaries like jQuery. But probably it's possible with JS.

Code Example:
http://stackoverflow.com/a/2625240

[vincentqb]

If long press is not an option, captions could be displayed just by tapping the image.

[David-Development]

Only needs to be tested on a real device.