I opened an issue on GitHub, but the NRF Connect iOS repo has not been updated recently. Here is the link: https://github.com/NordicSemiconductor/IOS-nRF-Connect/issues/118
Re-posting for this forum:
I have experienced for several versions of both the NRF Connect iOS app and NRF Connect SDK an issue where NRF Connect iOS cannot OTA DFU with MCUBoot. The NRF Toolbox iOS app succeeds in performing the OTA DFU update procedure. Both apps will sometimes timeout during sending the binary and succeed after retry when that happens. Specifically, the issue at hand is that NRF Connect iOS may not be able to initiate OTA DFU for the same sensor that NRF Toolbox iOS can.
Looking at the README on https://github.com/NordicSemiconductor/IOS-nRF-Connect-Device-Manager, it looks like NRF Connect iOS is using the wrong DFU mode.
One screenshot shows a failure on NRF Connect iOS that eventually results in a timeout (even after reattempt). The other screenshot shows the beginning of the logs from a NRF Toolbox success.
