Think about how you use your smartphone now and how 3G supplements its usage. You have access to almost everything you need and it comes to you in seconds when you ask. 3G is an efficient method of sending data to phones, but 4G is seen as the next big mobile feature.
This is understandable on tablets and laptops, but do we really need it on phones? Video (YouTube streaming), multi-player gaming and other data-intensive tasks do work well on a smartphone and it could be argued that we do not need enhanced speed. For more intensive tasks, the smaller smartphone screens diminish the experience anyway and so the idea that networks should concentrate on improving the reliability, capacity and speed of 3G networks makes a lot of sense.
3G for smartphones and 4G for larger devices would increase flexibility, offer speeds that suit the devices and potentially transform large parts of the industry for the better. Smartphone batteries can cope better with 3G, evidence suggests that they are currently struggling under 4G, and the entire experience would be enhanced.
4G may be the buzz-technology of the moment, but that does not mean that it is suitable for every type of mobile device.