I have a Network Extender that worked fine wtih 3G phones. Apparently it won't work with 4G LTE phones. I have been told that by Verizon that this is the case. There appears to be no way in the S4 from Verizon to disable LTE and lock 3G on. I have seen all sorts of discussion around apps that take you to a secret screen to swtich. Others say that it can't be done due to a limitation by Google. Bottom line is that my S4 is worthless at home due to poor signal coverage and preference by phone to link to very weak LTE signal. I would like to know how to lock phone in 3G mode for use with the extender as it seems to be very iffy.