Cellular modems are a top request for portable Linux and cyberdeck builds, and the sourcing landscape has finally matured enough to give builders real options. This article cuts through dozens of available modules and focuses on three battle-tested picks, starting with the SIMCOM A7682E: an LTE Cat 1 modem with 10Mbps download, 2G fallback, dual-SIM support, and a footprint pin-compatible with the ubiquitous SIM800. It connects over UART or USB, handles HTTPS and FTP natively via AT commands, and costs far less than the $100-per-unit pain of the 3G sourcing era.
The history here matters and the author lived it. Building ZeroPhone on a Raspberry Pi, they were burned by datasheet-less 3G modules, firmware dead ends, and a Stack Exchange moderator who deleted their sourcing question for being a 'shopping question.' That context explains why this list exists and why the criticism is credible. The A7682E gets real scrutiny too: the built-in speaker amplifier is described as puny, analog audio integration is awkward, and voice call reliability remains an open question since the author's own units had not yet arrived at time of writing.
The full article continues past the A7682E to two more modem recommendations, with the same format of specific features, known failure modes, and integration requirements. If you are designing a board that needs cellular data, SMS, or voice, the hardware detail and hard-won sourcing context here will save you time and money before you spin your first PCB.
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