Reboot your phone. Some live wallpaper apps and some apps in general will do that. I don't blame Android, I blame the developer. You can also email the developer so they are aware of the problem and so they can fix it. If not you can use another app if possible. Some developers are good and some are bad. Uninstall problematic apps and your phone will speed up.
I travel a lot and all the major cities have 4G. I had to spend the night in Dallas due my flight arriving late. The airline payed for my hotel but no WiFi. I used 4G on my cell phone. I don't know where you live but major cities, military bases, or well funded cities will receive 4G first. I live in Abilene, Texas and I'm sure we have 4G because of our well funded community and we have an Air Force Base here.