Speaking two (or more) languages is cool. Typing in two or more character sets is decidedly less cool. Bilingual speakers who know, say, English and Spanish can have an easy enough time typing since they share a (mostly) common Latin alphabet. However, English/Hindi speakers may have a harder time bouncing between scripts because they use entirely different character sets. Enter Google.
In addition to providing a regular Hindi keyboard (below, right) which takes up multiple pages of letters, this app also offers a transliteration keyboard.