In this comprehensive review we look at the service and flagship satellite phones from Iridium and Inmarsat, the Iridium Extreme and the IsatPhone 2.
Inmarsat IsatPhone 2 is the cheaper phone. Iridium Extreme is the more expensive phone. But while cost is a factor to purchasing one phone or the other, satellite phones are primarily used for safety and emergency. You should look at the benefits and downsides of each phone to make sure the satellite service you ultimately choose is best for your situation.
The Iridium Extreme is quite smaller than the Inmarsat IsatPhone 2. In addition, it’s lighter at only 247g versus 319g on the IsatPhone 2. The larger IsatPhone 2 does have a bigger screen, albeit screen size doesn’t mean as much when it comes to satellite phones as opposed to your conventional cell phone. The Iridium Extreme is looks more like a walkie-talkie, whereas the Inmarsat IsatPhone 2 is looks like one of your traditional wireless landline phones.
While the Iridium Extreme beats the Inmarsat IsatPhone 2 in size, Inmarsat’s new phone definitely wins in battery life. The larger IsatPhone 2 has a talk time of 8 hours as opposed to the Extreme’s talk time of 6 hours. Where the IsatPhone 2 really shines is the standby time, which is a staggering 160 hours compared to the mere 30 hours of the Extreme. If you’re not going to have access to another battery or charger for more than 24 hours, then the Inmarsat IsatPhone 2 is the better choice here.
When it comes to durability, both phones can definitely withstand whatever nature throws at it. Both phones are IP65 rated, meaning they’re dust, shock, and splash resistant. By splash resistant, the International Electro Technical Commission certifies that the phone will be “protected against low pressure jets of water from all directions”, like a low-pressure hose.
Despite this, the Inmarsat IsatPhone 2 can operate at colder temperatures. It’s certified to work at temperatures between -4°F to 131°F (-20°C to 55°C) while the Iridium Extreme is certified to work in temperatures ranging from 14°F to 131°F (-10°C to 55°C). As such, the Inmarsat IsatPhone 2 is a better choice if you’re going to be in temperatures colder than 14°F, up to -4°F.
Both phones have the essential features of most satellite phones – speakerphone, two-way SMS/email messaging, voicemail, and more. The Inmarsat IsatPhone 2 comes with Bluetooth for hands-free calling though - the Iridium Extreme does not. Both have backlit keypads and large buttons for very easy dialing in the dark, even with gloves on. As a whole, the only notable difference is the Bluetooth availability with the Inmarsat phone for hands free calls.
Iridium and Inmarsat have different satellite configurations that bring them services. Inmarsat has coverage through 3 fixed high-altitude satellites, 22000 miles above surface around the equator. As a result you can only use the Inmarsat IsatPhone 2 when there is a direct, unobstructed line of sight between the phone and the satellite in the sky above. The phone has poorer connection when you get close to the poles, and loses signal at the poles.
On the other hand, Iridium has 66 different satellites that are only a few hundred miles above surface across the globe. Iridium will get signal at the poles, unlike Inmarsat. Because its satellites constantly move around, the signal moves along with it. Iridium will make calls in open areas wherever Inmarsat also gets signal. But with Iridium, if you plan on making very long calls (10+ minutes) in these open areas there’s a very, very small possibility that your call could be dropped because the satellite you’re connected to fails to transfer your call to the next satellite in range. The moving satellites also means that if you’re in an area where your signal would otherwise be obstructed with Inmarsat, the satellites can move into your range without you having to move, allowing you to make calls with Iridium. But, if you make calls from these obstructed areas for more than say 5 minutes, the satellite could move away and you lose your call. Overall, Iridium has more coverage.
As such, the differences in cost between Inmarsat and Iridium come with differences in service. You should take the time to consider your situation as it relates to these pros and cons. If you have any doubts about which one to use, you can always feel free to describe your situation and ask Stephen for advice by emailing him at
The majority of people buy satellite phones for emergency use, and this is exactly where the new Iridium Extreme outshines the Inmarsat IsatPhone 2. Both phones feature an emergency button at the top of the phone. On the Iridium Extreme, the red SOS button at the top will send GPS coordinates and a distress signal to the GEOS International Emergency Response Coordination Center, which will alert local authorities of your whereabouts and maintain contact with the local embassy, first responders, and emergency contact members. This center is manned 24 hours a day throughout the year and can communicate in 200 languages, which means that in any emergency, you can assure that someone will be alerted to help. GEOS also provides additional Search and Rescue and Medevac services for less than 10 dollars per day, or a few hundred for the year. They offer evacuation and hospital benefits, up to $1,000,000.
Because Iridium has partnered with GEOS, signing up for these services is as easy as following the instructions on the Iridium website. Meanwhile, the Inmarsat IsatPhone 2 emergency button will send GPS coordinates and a pre-set text message to any pre-set phone number when pressed. That’s not to say that the Inmarsat IsatPhone 2 can’t be paired up with another outside 3rd party service that you can program the emergency button to, but you’ll have to find the service and set it up on your own.
In the end, Iridium’s partnership with GEOS has made emergency services more convenient and reliable to use in extreme situations. For those who think they made need the extreme services that GEOS provides, such as Search and Rescue or Medevac services, the Iridium Extreme is the way to go. For others who aren’t going to be in any significant amount of danger, but rather need a cell phone service to make the occasional call outside of cell phone range, the Inmarsat IsatPhone 2 is the cheaper choice.