You can use the following methods to program the modem and applications on the Nordic Thingy:53.
- Over-the-Air (OTA) update with the nRF Programmer mobile application
- USB (MCUboot) update with the nRF Connect for Desktop Programmer application
- External debug probe update with the nRF Connect for Desktop Programmer application
If you program applications with an external debug probe, you can use the nRF5340 Development Kit (DK) or any J-Link device supporting Arm® Cortex®-M33 as the external debug probe.
For more information, see Updating Nordic Thingy:53 firmware in Getting started with Thingy:53.