SIM Cards Post questions related to SIM card usage troubleshooting (that is, issues with your devices using our cellular connectivity services) Spacebridge This section of the forum is for questions about Spacebridge, our software that allows users to SSH tunnel into their cellular devices. This is critical for devices that do not have public IP addresses. Data, Carriers, Costs and Features Have questions about costs of data or what kind of connectivity options that Hologram has? Post that here. Issues with the actual connection to the network should be in more specific categories like the SIM Card category. LTE Cat-M1 & NB-IoT As many people know, Hologram provides the largest global coverage for cellular IoT devices. Expanding our support of 2G, 3G, 4G devices we now offer Cat-M1 and NB-IoT coverage in select markets and cellular partners.