It never fails that when you haven't brought a toy or other distraction for your child, you unexpectedly end up waiting somewhere praying that your child won't have a melt-down. But if you have a smart-phone handy, there are a few great edu-taining "time busters" that can keep your little ones entertained. Here are our four favorite sites to keep 'em busy (and learning!) during down-time; all provide a fun mix of "gaming," characters they know and love, and educational benefit (i.e. reading, shapes, colors, numbers, etc.).