CatholicTV: Free. Available only for Apple devices. Content available in English and Spanish.
CatholicStuffPodcast: Catholic podcast (and cool tshirts!). Frs. John, Nathan, Mike and Mike record from either Denver or Rome and talk all things Catholic. Posted once a week, usually on Thursdays.
Formed: Free: Available for Android and Apple devices. It's like a Catholic Netflix. See the link under Formed - Catholic Faith Online for log in details.
iBreviary: Free. Available on Android, Kindle, Apple devices, and WebApp. An electronic breviary, the book used to pray the Liturgy of the Hours. Uses same translation as the paper version. Also provides the Mass readings of the day, a short saint biography on feast days, and huge selection of prayers and blessings.
iMissal: $. iMissal is available for iPad, iPhone and iPod Touch, Mac.OS and now Amazon Fire devices. The iPhone & iPad versions are bundled together; purchase the app once and you get both versions.
iRosary: $. Available only on Apple devices. Fully-animated Rosary for iPhone and iPod Touch.
Laudate: Free. Available only for Apple devices. "The most popular and most comprehensive free Catholic App. Available in English and multiple languages. Huge resource library of Catholic Chaplets, prayers, Daily Mass Readings, Liturgy of the Hours, Stations of the Cross, Latin Rosary, etc. Multiple podcasts for daily meditations and Rosary. Daily Mass live video stream and more...."
Masstimes for Travel: Free. Available only for Apple devices. Official app of Masstimes.org. Find a Mass nearby, wherever you are, with directions. It often offers additional information on availability for Adoration and Confession.
National Catholic Register: Free. App for Android and Apple devices. A service of EWTN. Latest news, blogs, commentary and more, all from a faithful – and award-winning – Catholic perspective.
RelevantRadio: Free. #1 Catholic radio podcast app. Available on Android, Amazon Alexa, and Apple devices. Provides access to all the shows produced by Relevant Radio, available in live streaming or downloadable content.
RosaryPlusHD: $1.99. Available only for Apple devices. Pray the Rosary (Traditional, Dominican, Latin, 15 & 20 Decades), Seven Joys, Seven Sorrows, Divine Mercy Novena, Divine Mercy Chaplet, and St Michael Chaplet.
Universalis: $. Available for Android, Apple, Windows and Amazon devices. Has in-app purchases. Liturgical Calendar, Liturgy of the Hours, Daily Catholic Readings, Daily Mass Readings, audio versions and more. Good for priests and religious.
Vatican News: Free. Available only on Apple devices. Official site of the Vatican. Vatican News gives you the latest news and information on the Pope Francis and the Holy See.