Most low-end smartphones only feature 3G support because the cheap chip powering them does not support 4G (LTE). Qualcomm is aiming to change that with the announcement of the Snapdragon 210, the first chip in its class to feature LTE (and in both single and dual SIM forms). The Snapdragon 210 also supports carrier aggregation, allowing a download speed of up to 150Mbps. Microsoft/Nokia and other manufacturers have so far been limited to 3G at the bottom end of the scale - this announcement should mean LTE-capable budget Windows Phones in 2015.

From the press release:

Today, Qualcomm announced the Snapdragon™ 210 processor, making 4G LTE available in this class of processors for the first time...

The Snapdragon 210 processor will offer integrated, multimode 3G/4G LTE Advanced and LTE Dual SIM for entry-level smartphones and tablets. LTE Advanced means that this processor supports Carrier Aggregation (up to 20MHz)—another first in the 200 tier-- to help carriers achieve maximum 4G throughput (up to 150Mbps) via numerous RF band combinations. Dual SIM support is a popular feature in Asia and Europe, and Qualcomm is taking this feature to new heights by adding 4G LTE data support.

LTE accolades aside, the Snapdragon 210 is chock-full of mainstream features, integrated with an Adreno™ 300 series GPU, up to an 8 megapixel camera, and Full HD video capture and playback with support for native HEVC.

Qualcomm says that 2015 is a realistic time frame for seeing devices based on this. The only fly in the ointment is that users of low end devices are typically on low end connections, either pay-as-you-go or severely capped data packages, meaning that some of the benefit of LTE is lost. Still, with LTE becoming more ubiquitous and offering lower mobile latency, at least more and more people will be hooked into the mobile networks in this manner. 

PS. Qualcomm also announced a 3G version of this chip — the Snapdragon 208, with a dual-core processor and qHD display support. Presumably manufacturers can design for both and then slot in the one needed for a particular device?