[Chalkarts]

When using a thrown weapon do you use the agility and strength of the cyberarm or your natural strength&aglity?
Melee I’m pretty sure will use the arm.

I know it’s a newb question, but the whole cyber vs natural for certain checks thing is still bending me a bit.

[Tecumseh]

The most common interpretation would be to just use the cyberarm. See p. 455 of SR5:

Cyberlimbs have their own Strength and Agility ratings.
When a particular limb is used for a test (such as
leading an attack with your cyberarm), use the attribute
for that limb (natural or cyber); in any other case, take the
average value of all limbs involved in the task. If a task
requires the careful coordination of several limbs, use the
value of the weakest limb.

A strict GM might make arguments about the biomechanics of throwing and how it potentially involves non-arm muscles to provide torque and stabilization, but that's not a level of detail that most tables want to get into.