I got an offer in my email today for a $5 credit towards any books, comics, and more for Google play.
" Start reading on Google Play
$5 credit on us
Start reading on Google Play, where you’ll find new releases, classics, comics, and more. Plus, enjoy a $5 credit on any book over $5. Claim your offer below. Your credit will be applied at the payment screen.*"
https://play.google.com/store/books