Why my smartphone switch between 4G and 3G networks
The 3G network is probably set to push a smartphone to 4G if the phone is capable and LTE(4G) coverage is available.
- The interworking issues between several vendors (one on 3G and another one on 4G) can be the reason you smartphone switch from 4G to 3G.
- The smartphone can switch from 4G to 3G, GPRS or GSM to save battery when that is low. If there no 4G coverage or satured the carrier could balance traffic between different network available.