We get this questions all the time at our iPhone repair store. A lot of people don’t know what a digitizer is and whats its use and why is that so important to have a proper working digitizer for smartphones.
To start with a digitizer is some thing that converts the analog signals of the smartphones in to digital format. This digitizer is attached to the glass of the smartphone. Because the top glass and the digitizer are integrated together you cannot separate them. Even if you have a broken glass you need to fix the whole scree along with the digitizer and if your phone is not responding to the touch commands then too you need to replace the whole screen/digitizer.
The digitizer acts as the sensory part that receives the touch commands on the glass screen of the iPhone. The digitizer is thin and transparent. There is a good chance that people refer iPhone digitizer as iPhone screen or iPhone glass. These different terms are used to address the same product.