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Viber makes money via fees generated from its business account, subscription fees for international calls (Viber Out), as well as ads shown within the app. As for text messages, they are under 1Kb (125 B) per 500 characters. If you want to use Viber while you are connected to your cellular data, it will consume nearly 240 KB per minute up and down, and 14 MB per hour up and down. Viber requires either a 3G or Wi-Fi connection to work and if you’re not connected to a Wi-Fi network, it will use your 3G data to place calls or send texts.
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The receiver of your call doesn’t need to be connected to the internet however, they need to be in an area that can receive phone calls. Your carrier will not charge standard calling fees. You need to be connected to the internet (mobile data or wifi) to make a Viber Out call.
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