As of this morning, there were 5 free games available for download on my phone's PlayStation app. 2 of them were from PlayStation Plus, but 3 were not.
I had to click on the "All PS4" category to see them.
1.) Blacklight: Retribution || a competitive online multiplayer FREE TO PLAY First Person Shooter featuring unparalleled character customization depth and an innovative gameplay system that allows players to see through walls to make tactical decisions on the fly to keep combat fast and brutal. Guns, gear, and armor can be customized piece by piece to create the perfect load out. Blacklight: Retribution throws players into fierce battle over a dystopian future on over 10 maps with more than 10 gameplay modes!
2.) Contrast (PS+, normally $14.99) || a platform/puzzle game where you can move between a fantastic 3D world and a mysterious shadowy universe in 2D. You play Dawn, the imaginary friend of a young girl named Didi. Together, they will delve into a dreamlike and surreal 1920s world, inspired by the performance art world of vaudeville and film noir, and cradled by a jazzy atmosphere.
3.) DC Universe: Online || Free-to-Play! Join thousands of other players in a massive online action game set in the popular DC Comics universe. Create and customize your own powerful Hero or Villain and experience true action combat as you fight alongside and against legendary characters such as Batman, Superman, The Joker and Lex Luthor. Become a part of our thriving community at DCUniverseOnline.com!
4.) Resogun (PS+, normally $14.99) || Unleash a diverse array of devastating weapons including lasers, missiles, overdrive , and nova-bombs to blast hordes of enemies and rescue the last survivors from distant galactic colonies that are under ruthless attack from an evil alien invasion force.
5.) Warframe || They were called Tenno. Warriors of blade and gun - Masters of the Warframe armor. Those that survived the old war were left drifting among the ruins. Now they are needed once more. The Grineer, with their vast armies, are spreading throughout the solar system. A call echoes across the stars summoning the Tenno to an ancient place. They cummon you. Come Tenno, you must join the war.