The nRF Programmer allows users to upload precompiled firmware samples from the nRF Connect SDK to your Nordic Thingy:53 over Bluetooth® Low Energy (LE), without connecting to a PC or external programmer. This allows you to easily test out different applications and update firmware without the need of having physical access to the device.
Read more about Thingy:53 at https://www.nordicsemi.com/Products/Development-hardware/Nordic-Thingy-53