By now, most Android phones
have a 4G antenna -- but lots of 4G networks are spotty, and sucking down data
at that speed can drain your battery or put you over your monthly data
allowance pretty quickly. What's to be done? The easiest fix is to manually select
between 3G and 4G networks -- for example, maybe you only want to turn on 4G
when you're in an area that has good coverage, or maybe you want to force your
phone onto 3G to avoid draining your battery. Look for the "Mobile
networks" subsection of the Settings screen, then check "Network
Mode." You can set it to CDMA only (3G), or LTE/CDMA (3G and 4G). This
setting might vary depending on where you're living or what network you're on.