The official Playstation app is your basic one stop shop of sorts for everything you need to interface with your Playstation 4 system. It allows you to use the device you have it installed on as a second screen, you can send and receive messages to and from your friends lists, access the Playstation store to search for and buy new games, and you can use it to access the Playstation system guides, manuals, and the Playstation blog at a moments notice. you can also view your gamer profile of course, and view your trophies. You also get any incoming Playstation notifications about game invites, game installs, friends coming online and best of all you can use it as an on-screen keyboard for the PS4 so you don't have to use the D-Pad and buttons on the controller to type things out. The app is free, but you do need a PSN account and a PS4 to use it. You can grab the official Playstation app from the Play Store link.
Call Of Duty
If you're a Call of Duty fan then you should definitely have this app installed on your device to enhance the gaming experience on your Playstation. This one isn't specific to PS3 or PS4, and you can be used in conjunction with either console. You can use the app to join and manage Call of Duty Ghosts clans. Use the app to stay up to date on the latest Call of Duty news and events, use clan chat to communicate with clan members, and of course check your career stats. You can also use the app to optimize your loadouts on the go, which can prove beneficial so you don't have to do it later and can jump right into the game when you get home. Call of Duty is free, and you can grab the app from the Play Store link.
SC Blacklist: Spiderbot
This is the official companion to Splinter Cell Blacklist. Use the app to unlock exclusive Blacklist content, like Alpha Goggles for colorized thermal vision, Alpha Boots for increased protection against damage, and and transfer mobile currency to your copy of Splinter Cell: Blacklist. You can even use the app to control Sam Fishers bots, the Spider Bot, the Stealth Bot, and the Strike Bot, which are actually fashioned into a nice little mini game of sorts, and the money you earn through the mobile app is the currency you can transfer to the actual game. SC Blacklist: Spiderbot is free, and you can grab it from the Play Store link.
Assassins Creed Black Flag Companion
The official companion app to Assassins Creed Black Flag. Use the app to sync with your Playstation platform, and use it as a second screen to handle navigation so you don't have to leave the gameplay and the action. The app can handle tasks that you would otherwise have to move through the menus for, like accessing the world map. You can also use the app to find treasure maps, then find those locations in game and track down the riches. Also display messages and notifications from friends and find community challenges to participate in. You can even view all the animus database entries at any time. The Assassins Creed Black Flag companion is free, and you can grab the app from the Play Store link.
Battlefield 4 Commander
The official companion app to Battlefield 4 on your Playstation console. While in game, you can use the Commander to deploy war assets and deliver critical intelligence. Make sure to communicate with your squad with the supported full VOIP, even call in UAVs to scan the area for enemy activity and jam their radars using EMPs. Aide you teammates by calling in cruise missile attacks and devastating gunships, or lend support by sending in supplies to squads on the ground. Battlefield 4 Commander is free, and you can grab the app from the Play Store link.
Beyond Touch is the official companion app to Beyond Two Souls on the Playstation 3 system. You can use the app as a controller for the game instead of using the actual PS3 controller. It's a revolutionary new way to experience the game, and a fresh take on how to play using your Android device's touch screen instead of your controllers physical buttons. Beyond Touch is free, and you can grab the app from the Play Store link.
Ghost Recon Network
The official companion app to Ghost Recon Future Soldier on your Playstation 3 console. You can use the app to manage your squad on the go, view your stats, access your in game ghost feed, friend activity, challenges after using the app to enter sync mode and connect it to your console. Access your multiplayer stats and even create guns from the game in the apps gunsmith feature, and customize them any way you like. The Ghost Recon Network app is free, and you can grab it from the Play Store link.
Battlelog is a companion app to Battlefield 3 and Battlefield 4 on your Playstation console. You can use the app to stay connected to your friends who play the game. Check your stats and see what you have next to unlock so you're always on the top of your game even if you're not on home. View your detailed stats of past games called Battle Reports, compare yourself in the leaderboards, and view the mini-map in full screen on your tablet while your playing to get an edge on the enemy. You can also customize your loadout and view your rank up progress and stats. Battlelog is free, and you can grab the app from the Play Store link.
Metal Gear Solid V: GZ
The official companion app to Metal Solid V: Ground Zeroes for your Playstation console. Use the apps iDroid mode to open up the map and navigate through the games levels on your console, and call in support helicopters. You can also use the app to go back over the games intel and listen to the games music tracks. You can also enter into Mother base Mode, which is essentially a mini game where you build your private army, expand your base, and manage your forces to strengthen your troops. When inside Mother Base mode you can even sync it to the game to gain special troops and weapons. Metal Gear Solid V: GZ is free, and you can grab the app from the Play Store link.
Watchdogs Companion: ctOS
The official companion app to Watchdogs on your Playstation console. Use the app to connect with and play with any ctOS agent playing the game on their console. You can use the app to control all of Chicago cities police force, and you can use every tool at your disposal to challenge other players in game and attempt to shut them down. You can customize your own challenges and send them to your friends, take over a Chicago PD helicopter and track down your opponents, and dispatch varying types of police units around the city. Watchdogs Companion is free, and you can grab the app from the Play Store link.