Disable unnecessary push notifications
Push notifications can lead to higher data use, especially if you use a lot of interactive apps such as social network clients and messaging services. A number of apps also push promotional content that is not relevant to you. Modern Android devices and iPhone offer ways to disable push notifications through the system settings. You should also set your email to fetch mode and disable push unless you receive critical, time sensitive messages.
Track data use
The latest iterations of both Android and iOS allow you to track data usage for individual apps to identify the ones eating up your data allowance. You can even disable background data transfer (data use when the apps are running in the background to perform some task).
Disable auto-download on WhatsApp
Most WhatsApp users who're part of some or the other group receive multiple forwards in the form of pictures, videos and audio. When ever you receive these items you also incur data costs. Fortunately, you can choose to disable auto-downloads for all, none or a certain content type whenever you receive a multimedia message. You should ideally enable video and audio auto-downloads only when the phone's connected to Wi-Fi.
Do you watch a lot of videos on the go Or stream music Mobile data networks in India don't really offer good bandwidth plus data use is expensive. It's a good idea to subscribe to a paid plan of a music streaming service and sync your songs when connected to Wi-Fi. YouTube also lets you temporarily download music videos from most popular Indian record labels, valid for a period of 48 hours.
Use data compression
If you read a lot of online articles on your phone, it's a good idea to enable compression on your mobile browser. Google Chrome offers a 'Reduce data usage' setting to make the size of the web pages you visit smaller using Google servers. It even offers graphical statistics of data savings. Opera also offers Max, a free, data-savings and data-management app that compresses videos, images and media from apps and websites to reduce data use.