Clean Master, the No.1 Android optimization tool with junk cleaning and antivirus functions is free and trusted by over 850 million users worldwide. Making phones run like they're brand new all the time. Clean Master helps clean all types of junk files (photo junk, video junk, system junk, advertisement junk, and cache junk) to free up storage space. It can also clean junk notifications and free up RAM to improve your phone's speed and performance! It gives your phone powerful protection with functions such as Anti-virus and AppLock. By scanning and removing viruses, Clean Master protects your phone from safety problems and privacy disclosure.Clean Master Key Functions:JUNK CLEANER (JUNK FILES)Clean Master helps you clean all types of junk files (photo junk, video junk, system junk, advertisement junk, cache junk, and residual junk) on your Android phone, which can help boost and optimize your phone's speed and performance, as well as preventing your phone from running slow and lagging. It can also free up your phone's RAM (memory) and storage space, you can enjoy using a faster and speedier phone with just one tap. Clean Master - the best cleaner of all cleaning apps.Clean Master also provides customized and professional cleaning for many social apps like Facebook, Messenger, WhatsApp, Instagram and many more. With our professional cleaner, you can free up much more space from these apps easily and safely without worrying about deleting the wrong files. FREE ANTIVIRUSAnti-virus is another important function of Clean Master. As a virus scanner and cleaner, it can scan viruses on all apps (pre-installed or not), blocks and removes viruses from your phone to keep your device safe from viruses, trojans, malware, rogue software and protects your privacy. Clean Master provides the safest protection on everything in your mobile. Keep your phone safe and secure with Clean Master's free antivirus engine (ranked #1 by AV-TEST)! BOOST MOBILEOne Tap Boost feature of Clean Master can help boost mobile speed, optimize phone memory by freeing up RAM, and give you a faster and speedier phone. After boosting your mobile, run a speed test to see how much faster it has become.BATTERY SAVERClean Master helps save battery power and extend battery life. As a battery saver and booster, it can analyze your battery's status and kill background processes to save power and to extend your battery life.APPLOCKUsing Clean Master and stop worrying about privacy intruders and others trying to peek on your WhatsApp chat history or your Instagram photos! Use the AppLock function of Clean Master to protect your privacy with a PIN or lock pattern. Set a password or lock pattern for important apps such as WhatsApp, Youtube, Facebook, Messenger, Instagram etc. Lock and protect all your private data with Clean Master AppLock featureNOTIFICATION CLEANERClean Master sweeps and cleans junk notifications on your notification bar. It stops trash notifications from jamming and slowing down your phone, keeping your phone free from disturbing and annoying notifications.Other Optimization Features:CHARGE MASTER - Protects your battery from overcharging, displays charging status and application message on your lock screen when charging. GAME BOOSTER - Manage your games and accelerate loading speed of games.APP MANAGER - Back up and uninstall apps. Remove useless apps to free up your phone's storage space.CPU COOLER - Cools down your phone temperature and reduces CPU usage by stopping apps that cause device overheat. As well as extending your battery life! iSWIPE - Quickly access other apps and tools.Clean Master is compatible with most Android phones and systems, including but not limited to all devices from Samsung, Xiaomi, Sony, Moto, LG, TCL, HTC, Nexus, ZTE and more….Clean Master, the world's No.1 cleaner & antivirus app in Google Play.