Unlike minutes and text messages, which are relatively easy to quantify, understanding data usage isn't so simple. How many "megabytes" does it take to download a photo anyway?

Data from CTIA-The Wireless Association suggests that the average smartphone user consumes roughly 739 MB of data per month—that's much less than what's included in most wireless plans. This guide explains how data usage is measured, breaks down plans currently being offered by wireless companies, and helps consumers choose the best plan for them. A megabyte is a unit for measuring data. Whenever you send an e-mail, download a photo, or view a Web page, your phone is sending or receiving data. When it comes to cell phones, 1 MB of data is equal to roughly one of the tasks below: Even though typical customers use no more than 750 MB of data per month, many pricey data plans offer an even larger amount of capacity, measured by the gigabyte (GB). One gigabyte, which is about 1,000 megabytes, roughly equals one of the tasks below: According to CTIA data, consumers with smartphones—such as an iPhone, Android, or Blackberry—use an average of less than 750 MB of data per month. That's far less than the standard 2 GB of data recommended by cell phone companies. And 750 MB is no small amount. In fact, a quick analysis shows that it's enough data to send or receive 1,000 e-mails (250 with photo attachments), view 200 Web pages, post 50 photos on social media, download 10 apps, songs or games, stream 10 hours of music, and watch 60 minutes of YouTube videos.

No matter what carrier you're with, be sure to check with it frequently, at least during the first few months of your contract, to monitor your data usage. You may be able to access your data usage info by texting your provider, logging into your online account, or downloading a cell-phone app. Below is a sampling of typical data plans currently available from wireless carriers.

Tethering allows you to connect your smartphone to your desktop, laptop, or other device, acting as a modem and allowing the device to access the Internet through your smartphone's connection. If you tether, be sure to monitor your data usage closely, as services like Netflix can quickly send you over your plan's data limit. CUB created this chart as a helpful guide to define what your monthly usage is. Activate your smartphone's Wi-Fi connection to take advantage of wireless Internet that you might already pay for at home, and free Wi-Fi offered in restaurants, coffee shops and other public places. This will reduce the data your phone consumes over your wireless company's network, and potentially allow you to downgrade to a less expensive plan. Prepaid wireless companies, like Boost Mobile, Cricket, and Straight Talk, offer unlimited talk, text and data plans starting at around $45 per month with no contract. While smart phones are available, you won't have your pick of the very latest models. For more information, read CUB's prepaid cellphone fact sheet. CUB is a nonprofit, statewide utility watchdog organization that was created by the Illinois Legislature. If you have a question or complaint about a utility, call CUB at 1-800-669-5556.