Starting Monday, AT&T Inc. is replacing its current data plans with two new ones:

• The current plan provides unlimited data usage for $30 per month. If you’re a current customer, you can keep it.

• A new plan called DataPlus will provide 200 megabytes of data for $15 per month. If you go over, you pay another $15 for 200 megabytes. AT&T says this plan will suffice for people who surf the Web, send e-mail and use applications like Facebook. The data allowance is enough for 1,000 e-mails without attachments, or 400 Web pages, but only 20 minutes of streaming video.

• A plan called DataPro will provide 2 gigabytes of data per month (10 times more than DataPlus) for $25 per month. If you go over, you pay another $10 for 1 gigabyte. AT&T says 98 percent of smart phone users use less than 2 gigabytes, which is the equivalent of more than three hours of streaming video.

AT&T also is offering a “thering” option for DataPro users. For an additional $20 per month, users can utilize their smartphones as a modem to provide broadband connections for other devices.

“Tethering for iPhones will be available when Apple releases iPhone OS 4 this summer,” AT&T said.

The prices are in addition to the voice part of the plan, which costs at least $40 per month, plus taxes and fees that vary by jurisidiction. Data use over Wi-Fi does not count towards the limits.

Usage tools

AT&T is also adding some additional tools to let customers track usage:

• Customer text notifications on data usage. AT&T will send three text notifications after users reach 65 percent, 90 percent and 100 percent of plans. Customers will also be sent emails if AT&T has the user’s e-mail address.

• Data Usage Monitoring. iPhone and users of some other devices can check data usage through a downloadable “myWireless” application or call *DATA# from their phone. Usage information is also available at the AT&T Wireless Web site.

• Data calculator. The lets customers estimate mobile data usage and get “a better sense for which data plan is right for them,” AT&T said.

Calculator keys

The calculator includes eight categories with “sliders” through which you can calculate usage:

• One e-mail (text only): 20 KB
• One web page: 180 KB
• One App/Game/Song: 4 MB
• One e-mail with photo attachment: 350 KB
• One minute of streaming music: 500 KB
• Social media download/upload w/photo: 500 KB
• One e-mail with Word, Excel or Powerpoint attachment: 300 KB
• One minute of streaming video (YouTube™ standard quality):2 MB

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