android – Telegram Camera vs. WhatsApp Camera

this is 3rd time that I asked this question. two times ago, told me this is a wrong site.
if this question does not belong to this page, please guide me.
I’m new in android.
as you may know, Telegram and WhatsApp android application have the capability to use Smartphone’s camera.
both used the same came on Mobile, but Telegram has the graceful Image quality while WhatsApp has not.
my question is: what are the differences between these two applications, coding? libraries? …

do Telegram and WhatsApp use Built-in Android Camera Application or don’t

and more:

is it possible to write an application that has more Image quality and Android’s built-in camera application?