You would have to look on your phone to answer that question. In your settings under "Network & Internet" => "Data Usage" => "Mobile data usage" the amount of data each app has used should be listed. The labels of the categories may be different depending on the phone you use, but will likely be similar to what I have listed above.
it's all the web sites, social media feeds that use up data.
on a pc/mac, in myveizon, you can look at data usage day by day in your billing cycle to see which day/s had high usage!!
SCUBAMANSMOM, your network experience when using data is very important to us and we want to ensure you have all the ways to manage data usage. There was some good information to start with provided by rcschnoor and bearone21. Here is a web page that provides everything you need to know about how data is used, how to monitor it and ways to get more data. I have also sent you a Direct Message, so we can discuss the details further.
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