Satellite phones operate on independent satellite networks rather than terrestrial cell infrastructure, which means they function in areas where GSM has no coverage — including open ocean, remote coastlines and polar regions. From a safety perspective, satellite phones are significantly more reliable for distress and emergency communications in maritime environments precisely because they don't depend on shore-based towers. However, like any communications device, the security of the call depends on the network and encryption used. For GMDSS compliance, certain satellite communication systems are type-approved specifically for distress and safety purposes under SOLAS requirements.

The satellite phone antenna always needs a clear line of sight to the satellite. Structures, buildings, walls, and even trees that obstruct the view of the satellite can cause interference. Also, adverse weather conditions, such as heavy rain, can affect the satellite signal.

Satellite internet is an excellent way to get WiFi if you live in rural or remote areas where there is no GSM network. Inmarsat and Iridium charge based on data usage, so significant WiFi usage would become very expensive. For cost reasons, a viable option is Starlink.

Yes. The OCENS satellite phone email service allows you to send and receive emails cost-effectively through your satellite phone. There are also other service providers. Through faster satellite modems, you can use your own email normally.

Yes, you can send and receive text messages from satellite phones within that satellite network. Sending a message from a satellite phone to a GSM network works reasonably well, but it's not reliable. Messages from GSM networks to satellite networks usually don't get through. You can send text messages to satellite phones for free through most satellite phone operator websites.

Not yet. Low Earth orbit satellites will play a key role in expanding 5G mobile networks via satellites to the sea and other remote areas not covered by small cell networks. For end-users, satellites offer seamless expansion of 5G services from cities to airplanes, cruise ships, and other vehicles in remote locations.

Yes, satellite phones use SIM cards. Just as with conventional terrestrial mobile phone technology, satellite phones use SIM cards to transfer personal data and other device-specific digital data. Each satellite network requires its own subscription and SIM card.

Only the Thuraya X5 satellite phone offers hotspot functionality. Satellite side typically has so-called Bring your own device devices, where you can connect your own phone to the WLAN network to use data and make calls. However, these devices are not satellite handsets but rather modem devices weighing about a kilogram. Devices include the Iridium Go Exec and the Inmarsat network Cobham Explorer 510.