Packages for updating external applications can be generated by nRF Util for nRF5 SDK with the --external-app option.
Note
This functionality is experimental in the nRF5 SDK and not used in any examples.
For example, the following command generates a Zigbee package for external applications:
nrfutil nrf5sdk-tools pkg generate --hw-version 52 --application-version 0x01020101 --application app.hex --key-file key.pem app_dfu_package.zip --zigbee True --zigbee-manufacturer-id 123 --zigbee-image-type 321 --zigbee-comment good-image --external-app --zigbee-ota-hw-version 231
Because this package is intended for external applications as part of an update that does not contain a Soft Device or bootloader, the --sd-req option is not used (unlike in the example for generating a package under Zigbee packages).