[fellerts]

Fun project! Did you look into NTN (Non-Terrestrial Networks) capable modules as an alternative to Iridium? I haven't played with NTN myself, but it seems modules such as SIM7070G-HP-S support LTE-M/NB-IoT as well as NTN networks, and could in theory serve the purpose of your Iridium tranceiver as well as your LTE module. This technology hasn't matured yet, and I suspect the roaming tarriffs are expensive, but I don't know how it compares to Iridium.

[lxgr]

NTN seems to be only offered by geostationary satellite operators at this point, which unfortunately puts the use case from TFA out of coverage. See for example Inmarsat's coverage: https://www.inmarsat.com/content/dam/inmarsat/corporate/core...

I'm not even sure if Skylo is live with Inmarsat at this point, or if there are any other NTN providers covering oceans.