Understanding Cellular Speeds
When they need data, most people connect their iPhones to a nearby Wi-Fi network. Of course, there are plenty of us who are more mobile and need data while we’re out and about can’t always rely on finding a convenient Wi-Fi hotspot. Previous versions of the iPhone supported EDGE (Enhanced Data rates for GSM Evolution) cellular networks, EVDO (Evolution-Data Optimized) networks, and HSPA (High Speed Packet Access) networks, which have theoretical maximum download speeds of 0.38 megabits-per-second (Mbps), 3.1 Mbps, and 14.4 Mbps, respectively. EVDO and HSPA are known as 3G (third-generation) cellular standards.
The iPhone 5 goes further and also offers support for the HSPA+ (Evolved High Speed Packet Access) and DC-HSDPA (Dual-Carrier High Speed Downlink Packet Access) networks, which offer theoretical maximum download speeds of 21 Mbps and 42 Mbps, respectively, as well as LTE (Long-Term Evolution), which tops out at an eyebrow-raising 100 Mbps. Note that although some marketing types call LTE a 4G (fourth-generation) cellular technology, it in fact doesn’t quite meet the standards for 4G (which is why some folks refer to LTE as “3.9G”).
That’s the good news. The bad news is that super-fast cellular downloads mean that you might burst through your data plan bandwidth limit at high speed, as well. For example, if you have a 2GB monthly cap, if you managed to achieve 100 Mbps on an LTE network, you would bump up against your plan’s ceiling after just ...
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