Why not use the API of d-apps.net. You can just pull every app that is on sale out of their database...

You might check out d-apps.net. It offers all platforms, including Windows, and offers discount notification mails. Have a nice day!

Try d-apps.net. It has a button for discount alerts on the right side. You’ll receive a mail when your requested app is on sale.
Furthermore, it shows you the price-history of the app when it is in discount.

Hey, we just launched a site precisely for that: www.d-apps.net
All discounts for Android, iOS and Windows, many languages and countries. Optionally receive notifications if your favorite app is on sale. By the way, it also checks in-app discounts.
Cheers

Hey, we just launched a site precisely for that: www.d-apps.net
All discounts for Android, iOS and Windows, many languages and countries. Optionally receive notifications if your favorite app is on sale. By the way, it also checks in-app discounts.

Cheers