Of course, it’s all either displayed in figures with total remaining gas-time prognosis, or you can opt for a graphic of a scuba tank that changes colour too. That’s the beauty, and I mean real beauty, of it.
I called it the iPhone of diving computers when I first reviewed it (February 2010). That’s because of the coloured display made possible by Thin Film Technology (TFT). You can read that review on Divernet.com

Wireless Integration
Since the Icon HD came out, smart and Android phones have entered the market, and the computer is now offered with wireless gas integration.
It’s taken a while, and I guess Mares spent that trying to get round the Scubapro patent.
I know that Suunto tried to do the same, and I don’t know whether it was successful or not.
I do know that the Mares transmitter unit that plugs into the high-pressure port of a regulator first stage is quite a brute compared to the Scubapro/Suunto versions.
The colour display takes quite a lot of battery power so, before I could even get it to turn on, I had to charge its lithium-ion battery.
This can be done from a normal power socket, or from the USB socket of a computer.
It takes a little longer to pair up with its transmitter than some other computers, so you need to be patient. Once paired, it stays paired.
I never had any doubts about its ability to render a tank-pressure display on the dive.
The Icon HD can be used as an air or nitrox computer, or in gauge mode. It can be set for three different nitrox mixes per dive, and setting is as easy as using an Android phone.
The display, set behind clear mineral glass, is about the same size.

In the Water
Other than near the surface, when bright sunshine might compete with it, the display of this computer is as readable as any other available. It has the benefit of colour as well as contrast. At night, it’s simply phenomenal.
The deco requirements seemed identical to those of the Suunto computer I used alongside it. This is not surprising, because they both use examples of Bruce Wienke’s RGBM algorithm, adjusted for leisure diving.
The significance of any information displayed has its priority denoted by the colour in which it appears, hence the colour groupings of the different tank pressures. Like any Android phone, iPad or digital notebook, this item of equipment also has features available far beyond the core requirements.
All stops are predicted. A safety stop is indicated in green, deco stops in orange, deep stops in blue and maximum operating depth (MOD) in grey. Disaster warnings are red. When using two or three nitrox mixes, the graphic for the MOD is displayed in various shades of blue.
Pressing one of the four buttons made secondary and alternative displays available too. You can look at a pretty graphic profile of your dive so far, with mandated stops if appropriate, and download your own maps of dive sites and even photographs with which to irritate your buddies on long deco-stops.
In fact you could waste your dive playing with this computer rather than seeing what you originally came for. The only downside is that you need to charge it every night on a dive trip, because the charge appears to be sufficient for only around three long dives.
I wrote last time that I would have awarded this computer full marks if it was gas-integrated. Well, now it is, and I have.

Atomic Cobalt, £999
Uemis Zurich, £999

PRICE £1069 (upgrade from older version, £400)
NORMAL IN-WATER DISPLAY Depth, remaining no-stop time/ascent time, CNS loading, dive time, ascent rate, oxygen exposure, nitrox mix, water temperature
ALTERNATIVE DISPLAYS Dive profile plus profile including deco-stops; all stops including deep, deco and safety
LOGBOOK Yes, with graphic profile
MODES Air, nitrox, multi-nitrox, gauge
CONTACT www.mares.com
DIVER GUIDE width=100% width=100% width=100% width=100% width=100% width=100% width=100% width=100% width=100% width=100%