Congrats on the new LG G2. I have one myself and I absolutely love it. I would be more than happy to explain data usage. Anytime you need to make a connection to the network retrieve information is when you use data. When you access the internet browser, sending and receiving e-mails, downloading applications you are using data. Some applications use data when you use them, such as YouTube, Pandora, and Netflix. It is always a great idea to connect to WiFi where available. This is how I effectively manage to stay within my data allowance.
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