It’s getting to be a monthly tradition. The Amazon Appstore for Android is once again offering more than two dozen normally paid apps for free for a limited time.

The promotion started yesterday and ends today. In sum, there are 30 apps marked down to nothing. Most work on just about any recent Android device, though one is a “Kindle Edition” for Amazon tablets only and another was made exclusively for Amazon’s new Fire Phone.

The normal prices of the apps range from $0.99 to $29.99. Some highlights include:

Oxford Advanced Learner’s Dictionary, 8th edition (normally $29.99): This dictionary explains 184,500 words, phrases, and meanings with 3,000 keyword entries, 1,300 illustrated words, 116,000 example audio sentences, and more than 57,000 synonyms and antonyms.

Essential Anatomy 3 (normally $24.99): Learn all about the human body with this app’s 3D interface.

Carcassonne (normally $4.99): An adaptation of the wildly popular designer board game, Carcassonne for Android includes one expansion pack (The River II) for free and offers several others through in-app purchases.

Daily Workouts (normally $3.99): Combining five different exercise apps, Daily Workouts includes more than 100 exercises to guide your fitness regimen.

Instapaper (normally $2.99): This app strips the custom formatting of most webpages, which can then be read offline with adjustable fonts, text sizes, line spacing, and margins.

Sonic & SEGA All-Stars Racing (normally $1.99): Sonic is awesome. Racing is awesome. What more do you need?