How Much 3G Data Is Your Smartphone Using?

I don’t often look at my cellular phone bills, but I happened to glance at the latest one from T-Mobile. My first full monthly billing cycle didn’t show anything out of the ordinary, but the monthly data usage happened to catch my eye. I thought I chewed up more than 437 MB of mobile broadband, but I’m sure that T-Mobile keeps accurate records. After thinking over my usage patterns, I recalled the recent post James wrote in which he asked about Wi-Fi usage on smartphones. That’s when I realized my Wi-Fi pattern at the home office greatly impacted my overall smartphone 3G usage. But to really see how much of an impact there is, I’ve turned off the Wi-Fi radio on my Nexus One (s goog) and I’m leaving it off for the remainder of my current billing cycle, which is about three weeks.

I’m mainly curious what life would be like without Wi-Fi, as well as what the impact to the phone’s battery and the overall experience would be. Obviously, there are wireless hotspots all over the place and I’m not recommending that anyone walk down this path with me. Besides, there’s plenty of evidence that shows how smartphones are fueling the demand for Wi-Fi. This isn’t an attempt to buck the tide, I’m just experimenting.

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I’ve already seen one impact — the battery on my Nexus One is draining faster, although I did order a spare battery today — they’re now available direct from Google for $25 each. Having a second battery for devices is a common practice for me and not related to my 3G lifestyle. But when home, my Wi-Fi radio is active and I can stretch my phone usage through a full day, even though it’s my most used device when I’m not in front of a computer. But over the past few days while using 3G-only, I’m making it to around dinnertime with the device. That shouldn’t come as a surprise, but again, it’s nice to see some measurable indication of the drain. I’m not concerned about hitting any 3G bandwidth cap — the base data plans for smartphones in the U.S. are generally unlimited at this point. It’s the data plans for larger devices like netbooks and notebooks that come with the 5 GB monthly cap. With a larger display and a less-limiting operating system, these computers are likely to eat through more mobile broadband over the course of a month.

Again, I’m not advocating anyone else wean their smartphones off of Wi-Fi. Why wouldn’t you use a free or low-cost alternative to 3G that’s often faster? But I am curious if you’ve looked at your own 3G usage. How much 3G bandwidth did your smartphone consume last month or during your last billing cycle? Is it more, less or about what you expected? I’ve broken the smaller amounts down into chunks because I suspect very few folks are actually using more than 1 GB of 3G data on their smartphones. Unless they tether for modem use, of course. ;)

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