story and photos by Steve Wilent, editor, The Forestry Source (reprinted by permission of the Society of American Foresters)

Cedar Tree Technologies’ CT4 rugged cell phone (left) and CT7 tablet.

Cedar Tree Technologies’ CT4 rugged cell phone (left) and CT7 tablet.

Which type of handheld computer or tablet is best for working in the woods: “rugged” or not rugged? The answer depends on who you ask. Some foresters say rugged devices are worth the higher price, as they safeguard hard-won data and are likely to last longer. Others maintain that today’s handhelds are inexpensive and easy to replace, so why pay $1,000 or more for a rugged tablet when one can buy a handful of expendable tablets for the same price? Earlier this month, Cedar Tree Technologies sent me two of their new rugged Android-based handhelds to field test. My take is that these durable devices and their relatively low cost make a strong case for the “rugged is better” position.

Cedar Tree, which is based in Corvallis, Oregon, was born in August 2014 as a spinoff of Juniper Systems, maker of rugged handheld computers such as the Allegro and Mesa (see “Juniper Systems’ Mesa Notepad Opens Touchscreen Territory,” The Forestry Source, November 2011). Cedar Tree’s rugged handhelds, both of which run on the Android operating system, are the CT4, which is roughly the size of a typical cell phone, and the CT7, a tablet with a 7-inch screen.

Except for the ruggedized housings, each unit will be very familiar to users of Android cell phones and tablets. Each comes with a standard collection of apps and has 1.2-GHz quad core CPU, GPS antenna, fore and aft cameras, Wi-Fi and Bluetooth connectivity, and SIM card slots for adding cell-phone service. The CT7 has one SIM slot, while the CT4 has two, which allows for the device to have two phone numbers.

The Cedar Tree phones can use:

  • 2G (second generation) GSM (Global System for Mobile Communications) networks, primarily offered by AT&T and T-Mobile.
  • 3G (third generation) WCDMA (Wide Band Code Division Multiple Access) technology, which is used by most cellular networks.

2G connections consume less battery power but do not provide Internet access, as 3G connections do. If you don’t need 3G, you can change the mobile network settings option to “Use only 2G networks,” which helps save battery power. One drawback of the units is the Cedar Tree phones cannot provide the faster 4G service as many of today’s cell phones do.

The Cedar Tree devices do not come with cell-phone SIM cards (subscriber identity modules) that are necessary for making calls. They are “carrier unlocked” devices, so you can buy a SIM card from AT&T, T-Mobile, or compatible third parties. Via the Accessories section of Cedar Tree’s web site, you can buy one of the latter, an “H20 Wireless AT&T SIM With Talk, Text, & Data” renewable SIM card that provides 30-days unlimited talk and text with 500 MB data, with no contracts or additional fees. Cost: $30.

Cedar Tree’s CT4 and CT7 IP68 and IP67 ratings, respectively, making them waterproof.

Cedar Tree’s CT4 and CT7 IP68 and IP67 ratings, respectively, making them waterproof.

Hard Wear

Cedar Tree claims that both the CT4 and CT7 are fully submersible and have an Ingress Protection rating of IP68 and IP67, respectively. IP ratings are based on International Protection or Ingress Protection codes published by the International Electrotechnical Commission. The first digit after IP denotes the ability to withstand solid foreign objects, such as dust; the highest rating of 6 indicates “No ingress of dust; complete protection against contact (dust tight).” The second digit describes the level of protection against water; a rating of 7 indicates that “Ingress of water in harmful quantity shall not be possible when the enclosure is immersed in water under defined conditions of pressure and time (up to 1 m of submersion),” while a rating of 8 indicates that such protection is effective at depths greater than 1 meter. The company also says the units are able to withstand shocks (such as being dropped or subject to intense vibrations); however, no shock-resistance rating is provided.

The company’s web site shows photos of the units partially submerged in water. Naturally, I had to see for myself. A nearby creek provided an opportunity for this test. After submerging them fully or partially for about 20 minutes, the devices worked as before. When they were fully or partially immersed, icons on the screens oscillated at times and sometimes apps opened themselves. The screens didn’t like the cold water, but of course one would not use the devices while submerged. This test, and my use of the devices in the rain, tell me that they are well suited for working in the woods in any weather. They also showed no ill effects from being dropped into my daypack and thumped a bit when I set the pack none too gently on the stones on the bank of the creek.

Would I repeat these tests with my non-rugged iPad Mini or cell phone? Of course not. An Otterbox, SnowLizard, or other rugged third-party case might offer similar protection, but having the ruggedness built into the Cedar Tree devices is a distinct advantage, in my book. I have yet to use an add-on case that didn’t impede using the screen or buttons to some degree. What’s your favorite case? Let me know.

Rock Music and Other Features

One Cedar Tree feature that may be either a blessing or a curse: an FM radio receiver. Like many other phones, you can start an FM Radio app, pick a station, plug in headphones, and listen, just as you would with any other portable radio. (Your choice of music may be crucial. I tuned the CT4 to a classic rock station, and on another occasion set the CT7 to KMHD, Portland’s all-jazz public radio station. I noted a marked decrease in my work productivity when distracted by the latter station. Yet I recall one day long ago when I wore a Walkman — remember those? — while marking timber. On that day, with the help of some 1970s rock, my productivity was higher than normal.)

Of much more import are the CT series’ batteries. The company says they provide “All-day battery life” and that the CT7 “Operates for up to 20 hours on one charge.” I did not use either device for 20 hours straight or even for 8 hours at a time. However, battery power on both units lasted for nearly a week on one charge, with occasional app usage (Esri’s Collector, Google Maps, GPS Essentials, etc.) and long periods on standby with cell, Wi-Fi, GPS, and other processes on. At one point, the CT4 reported that it had been on for six days, 20 hours, 30 minutes, and had 17% of its charge remaining. I reckon that either unit would easily last though a day’s work in the woods.

Cedar Tree’s documentation makes no mention of the accuracy of the CT’s GPS receivers, so I assume that they are standard 5- to 10-meter receivers common in other cell phones. GPS Essentials reported calculated accuracy of 16 to 84 feet, depending on the density of forest cover. Note that Cedar Tree also sells the Garmin GLO Bluetooth GPS receiver as an accessory for $99. According to Garmin, the GLO is capable of 3-meter accuracy. The GLO is also available from numerous retail outlets. I ordered one from Amazon, also for $99—look for a review in a future edition. Robert Davis, Cedar’s director of product management, told me that the company is working on a GPS Trek accessory package that will include a GLO and a pole on which to mount it. This, too, may be the subject of a future Field Tech article.

Other features worth a mention: the CT’s Gorilla Glass display screens respond well to a finger, gloved or not, and stylus (not provided). The screens are bright enough to use in direct sunlight, but, as with all screens, glare and reflections of the sky and background can be an annoyance.

The rubber covers over the USB and headphone ports are necessarily tight-fitting. On the CT4, I had to use the screwdriver tool, provided for accessing the SIM and Micro SD memory card slots, to pry up the cover.

No user manuals came with the devices and I could not find them on the company’s web site. The web site does offer a few useful Tech Briefs such as “CT4 SIM Slot Management” and “Power/Battery Management on a Cedar Device.”

One quirk of the CT4 is that the on/off button is located on the lower left side; all other Android phones and tablets that I’ve used have the button on the upper right side.

The CT7 comes with a sturdy strap attached to the back that is handy for holding the device while using it. The CT7’s case has slots at each corner to which one might attach an additional strap or lanyard, but without a user manual, I’m not sure if that’s what they were designed for.

Bottom line: I found no significant weaknesses in the CT4 or CT7 hardware, and plenty of strengths, especially the units’ ruggedness and prices. The CT4 sells for $489, the CT7 for $899, from These prices are similar to what you might pay for a non-rugged cell phone (one with 4G cell service, however). In my opinion, either of the Cedar Tree handhelds would be an excellent value for foresters.