Should I upgrade to 4G cell booster, or will older 3G amplifier work?
This depends on your exact situation. The benefit of 4G service is currently the speed at which the 4G network can download and upload data. 4G service does however not do anything to enhance voice calls for the majority of North American cell phone customers unless your carrier has switched its voice traffic to voice over LTE (VoLTE).
If you do have a 4G-capable phone, a 4G data plan and you upload or download a lot of data, you probably need a 4G cell phone signal booster or amplifier. By the way, both "signal booster", "signal amplifier", and even "signal repeater" mean the same thing.
If you however primarily use your cellphone for voice calls and texting, a 3G booster will do the job if your carrier AT&T, Verizon, T-Mobile has not switched its voice traffic to 4G LTE. Both types of boosters are compatible with all cellular devices, i.e. a 4G phone can be used with a 3G booster and vice versa.
If you wish to upgrade your 3G model amplifier kit to 4G model amplifier kit, read about our cell phone signal booster upgrade policy.