How to protect our smart phone from virus

Now a days in internet one of the major problem is virus due to this virus A mobile virus is malicious software that targets mobile phones or wireless-enabled Personal digital assistants (PDA), by causing the collapse of the system and loss or leakage of confidential information. As wireless phones and PDA networks have become more and more common and have grown in complexity, it has become increasingly difficult to ensure their safety and security against electronic attacks in the form of viruses or other malware. 

This hackers installs this virus in such as
1.messages
2.App
3.Bluetooth
4.Downloading
1.due to the virus our personal data the data which is stored in our smartphone is in non privacy and our mobile in dangerous condition
My opinion 360 security is the best app to protect from virus for smart phones Free Security Protection and Speed Booster for Android Phone
Trusted by 200 million users, 360 Security is the only all-in-one speed booster and antivirus app that optimizes your background apps, memory space, junk(cache) files and battery power, while keeping your device safe from virus