To clarify my thoughts...
I run the phone on Wifi while at work if not in use. There is a Wifi network, it connects, but it is non-functional due to a password restriction. This saves battery life. However, the phone can only do non-network functions, or receive/send calls, or receive texts (sending is sporadic). Receiving email notifications is sporadic, but they usually can't be opened.
If I want to use the phone, I must shut off the Wifi, allowing it to switch to 3G/4G. Signal is a little iffy in the basement for logical reasons. Sometimes, roughly 25% of the time, the phone refuses to load anything. It returns a steady stream of network errors, connection refused, could not load, et cetera. This only ends when the phone is rebooted.
It is most common when I leave the area, passing beyond the Wifi range, shutting off Wifi, and trying to open Google Maps for traffic data. The program hangs, force closes, hangs a second time, sometimes a reboot is needed before 3G will restart. In the interim, it runs on 1X.
When I come home, I enable the Wifi, because I have almost no Verizon signal at my house, 1 bar or less, never 3G/4G. Sometimes, perhaps 10% of the time, the phone refuses to acknowledge the wifi, and returns the usual panoply of connectivity errors. Again, the only cure is a reboot, after which, it works happily.