I thought that board looked interesting. Looks like a $50 cellular board, includes 500MB of data over 10 years (though with missing fineprint according the the

I thought that board looked interesting. Looks like a $50 cellular board, includes 500MB of data over 10 years (though with missing fineprint according the the HN thread). Might not be a terrible board to design around. Though adding it to your BOM will make your final retail cost on the order of $450. Some creative googling got me this, for a different starting point. Looks like it might be a useful project writeup dealing with SDR and connecting to some cellular sources. https://www.blackhillsinfosec.com/intro-to-software-defined-radio-and-gsm-lte/ https://www.blackhillsinfosec.com/intro-to-software-defined-... I'm not sure how common open SDR hardware is, though some forum threads seem to suggest the Hackrf schematics are here, and are meant to be replicated: https://github.com/mossmann/hackrf https://github.com/mossmann/hackrf I think one of the big problems is ultimately going to be dealing with phone companies. I think that will ultimately stymie any open efforts in this space, since at the end of the day, you need someone to accept your cellular traffic.