Open your Google Play app and check under notifications to see if you have a coupon for $4 off any $4.01+ ebook, good through 12/16.
For example, The Jewish Nation of the Caribbean will be $3.99 after the coupon, just a bit less than it will set you back on Amazon 😉
You can find books under $5 here.
What book will you get with the coupon?
Not sure how widely this is targeted, but 2 of my accounts had this promotion. It included lots of books sold by Amazon. I bought 3 on each, and the lowest price of the 3 was free. It shows up, for instance, when you click on Nikki Haley’s new book.