Here is a phone from the mid 90s, the Ericsson GA628. Here visible is the front of the unit with keypad, & single line monochrome LCD for number display.
Here the battery is removed from the phone, showing the SIM card socket. At the top under the antenna stub is the socket for an external antenna.
Here the front is removed from the phone, PCB on left, rear of keypad on right. Microphone is at bottom of keypad, with speaker at the top. Top right of the PCB is the ringer buzzer, left is shield for RF amplifier.
Here is the back of the main PCB, RF sections on left & centre. Processing & memory on right.
This phone had a Ni-Mh battery, before Li-Ion batteries were introduced.
The LCD from the front of the phone is shown here. A simple dot matrix single line unit.