Android is the most popular firmware which has a largest collection of android apps and counting. Android not allow us to only customizable apps but also offer for multitasking. We can run more than 1 apps in the same time.
whatsapp messenger is one of the best messenger app that allow you to chat with your friends, share images, videos, location, etc. It also allows you to create your own friend groups for mass communication. The biggest headache for the people who are using dual SIM mobile phones and wanted to have separate whatsapp accounts for every number. Unfortunately this is not possible with simple whatsapp app.