In 'peripheral_uart', where does the BLE Tx data go?

I am confused about where the data sen to the output of the 'peripheral_uart' (Tx) goes when one uses the Serial Terminal to type in text.  Eventually, I want to be able to send advertising data that my device receives to my iPhone and I thought that what was being sent could be seen in the Logger on my iPhone (in nRF Toolbox, UART Rx/Tx).  When I type something into the serial terminal I see that it makes it to my iPhone (it is in green text) followed by a "received" message.  But this, now I think, is just what is coming in (what the Rx would see).  Where is the Bluetooth Tx output?  In the end I want to send my advertising matches to the iPhone but for now I would be very pleased if I could do something simple like just repeating all data the Bluetooth receives three times for each character on the Tx that comes in the Rx (proving I have control of what is sent out based on what is coming in yet modified).  This software test seems like it ought to ne simple enough to write.  I was hoping the Logger tool on the iPhone would only show the output but that doesn't seem to be the case (it appears to show the input).

I apologize for my ignorance ahead of time but I seem to be misunderstanding something that should be simple.

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