Amazon again offers its Prime members one early release Kindle eBook per month for free as part of its Kindle First Program. That's $6 under the list prices of these books, which are otherwise only available as preorders. Deal ends April 30.

Each month, you can choose from one of six new Kindle eBooks that are selected by Amazon's editors in advance of the books' official release dates; this month's titles include Deliver Her by Patricia Perry Donovan, The Secret Healer by Ellin Carsta and Terry Laster, and The Eagle Tree by Ned Hayes.