T-Mobile SDA Smartphone Review

by Reads (64,327)

T-Mobile’s newest import from Europe, the SDA smartphone, features almost everything you could think of jamming into it’s tiny little case, including quad-band GSM/EDGE, WiFi, and a QVGA screen, all at an absurdly low price.

The SDA is, like most Windows-based phones available today, a product of High Tech Computer of Taiwan. The device that T-Mobile sells as the SDA is also known as the HTC Tornado, and is sold under a variety of different names, some including slight design changes. While this is primarily a review of the SDA, most of its contents also apply to other Tornado variants, such as the i-mate SP5m, QTEK 8300, and Xda Xphone.

The Tornado is also very similar to the HTC Faraday, better known as the Cingular 2125, that we recently reviewed. While the specs are nearly the same, the SDA includes Wi-Fi while the 2125 does not. Differing software implementations for the two devices may also result in varied performance.

Design & Construction

While the dimensions are almost identical to the Cingular 2125, the more rectangular design of the SDA makes it seem larger at first glance. The SDA bears a slight resemblance in shape to its European ancestors. Over there, there have been several devices in the SDA family, with the most recent one being the SDA Music, called that for its dedicated music buttons. This is the model that’s sold in the US, under the simplified SDA name. Just so we have that out of the way.

The new SDA features the same top-side hump as the 2125. The hump is supposed to be an antenna housing, allowing for better radio performance than other similar phones. From my experiences, detailed under Communication, it does this quite well. So just think of it as a signal-boosting hat for the device. Mounted forward of this are the power button and infrared port.

Unfortunately, like the Cingular 2125 before it, the SDA lacks a simple way to turn it off. Pressing the power button just brings up a list of options including locking the device, turning off the phone radio, and changing ring profiles. As it happens, the only thing that the power button does that is actually related to the device’s power state is turn it all the way off, completely shut down including the phone. Not much use in that.

The keypad and buttons are, for the most part, comfortable to use and press. The exception is the top row of keys below the screen, which include the left & right softkeys, back, and home buttons. These are so small that they’re more difficult to press than they should be. Navigation was a bit more difficult, as compared to the 2125, because of this.

Under the battery, we find the phone’s miniSD slot (center) and SIM card holder (right). The SIM mechanism is identical to the 2125’s. Rather than just sliding the SIM up against the contacts, you mount it on a little metal swinging door, which then latches into place. It’s actually easier to deal with than the standard system, a benefit if you’re going to be swapping SIMs often.

Build quality is excellent, but that’s par for the course on an HTC device. There’s hardly a single complaint I could make about the construction itself — it’s top notch. The design has a few kinks, but on the whole is mostly comfortable.



Processor: 195 MHz TI OMAP850 processor
Operating System: Windows Mobile 5.0 for Smartphones
Display: 240 x 320 transmissive/reflective LCD
Memory: 64 MB flash (16 MB available); 64 MB RAM
Size & Weight: 4.53″ long x 1.82″ wide x 0.69″ thick; 3.74 ounces
Expansion: Internal MiniSD slot
Docking: Mini USB port
Communication: Bluetooth 1.2; IrDA; 802.11b WiFi; Quad-band GSM/GPRS/EDGE (Class 10)
Audio: 2.5mm headphone/headset jack; internal speaker & microphone
Battery: 1150 milliamp-hour replaceable Lithium Ion battery
Input: T9 text via numeric keypad
Other: 1.3 megapixel digital camera



In common use, the 195 MHz TI processor propels the SDA along at a very solid clip. Too many running apps will bog it down, but you have to have at least four or five programs or more going before that happens. The processor manages to be both fast and energy efficient, an ideal balance for a mobile device.


Operating System

The Windows Mobile Smartphone Edition isn’t nearly as much like Windows Mobile for Pocket PCs as you would expect, given the name and the fact that there’s some application compatibility. The WMS flavor operates more like a phone, with a lot of numeric keypad shortcuts. These aren’t required to operate it; you can do pretty much anything with just the main buttons and joystick, but using the shortcuts can dramatically speed up operations. If you went at the device cold, and ignored the names of things like the “Start Menu” and Internet Explorer, you might never notice that the two interfaces are related.

While Windows Mobile 5.0 for Pocket PC can run Smartphone applications, the reverse isn’t true. If you try to install a PPC application onto the Smartphone, either manually or using an install file, you’ll get a message saying that it’s not compatible. Only apps which are specifically Smartphone compatible will operate.

The SDA also comes with the ability to run simple Java applications, called “midlets,” the kind that you find on ordinary phones. I tested it with Opera Mini, as well Google Local. Both ran satisfactorily.



The LCD on the SDA is dazzlingly bright, identical to the 2125’s. This can be a little annoying if you’re using it in low light, because there’s no way to adjust the backlight to a more appropriate level. On the bright side (no pun intended), the added punch makes viewing the screen in daylight all the much easier.



The SDA is seriously deficient in memory, at least if you intend to install any number of applications. The system claims 16 MB of Storage is available, but in the default configuration the user only gets about 11 of that. Unless you only intend to use the built-in applications (and even then, no media or downloaded files), you will emphatically need a MiniSD memory card. Since I didn’t have one, I ran critically low on memory several times. Let that be a lesson to you — there’s no such thing as too much memory.


Size & Weight

At first, the SDA looks larger than it is. This is primarily an illusion, though is strikingly small and light. It’s really not much bigger than an ordinary phone, and weighs just 4 ounces. If you’re accustomed to carrying a standard mobile phone, you could replace it with the 2125 and never know that you had changed devices.



With the miniSD slot being under the battery, you don’t have any real expansion options on the SDA other than additional memory. Then again, with internal Wi-Fi, there’s little point in having a MiniSD Wi-Fi card. The device is rated for miniSD cards up to 1 GB, but should be able to handle a 2 GB card without difficulty.



The SDA lacks for a desktop charger in the package, offering only a USB cable and mini-USB charger. I’m sure this could be corrected with a minimum of third-party effort, if you’re so inclined, though at the time of this writing I didn’t see any such cradles available.

The upside of using a mini-USB plug for docking and charging is that any mini-USB cable will also serve as a sync-and-charge cable. And as long as you have a cable, any USB port is a charger. You can also share cables and chargers with any other devices that have a mini-USB port for charging.



One of the biggest things that makes the SDA stand out is that it has built-in Wi-Fi, a rarity for Windows Mobile Smartphones. Unfortunately, this isn’t as big an advantage as you would think.

I found the SDA’s Wi-Fi implementation to be distinctly substandard. The configuration applet allows you only to select between “Work” and “Internet” profiles for a given network. There’s no option for manually configuring IP address, routers, DNS servers, anything. Basically, if you don’t have DHCP fully implemented on your network, you’re out of luck. Since my home network runs on static IP addresses, I was unable to configure the SDA to use it.

As much as I am a huge fan of Wi-Fi, I’m hard pressed to see this as a great loss, at least for most things. The screen on a smartphone of this type is so small that any web browsing is minimal at best. Most Internet access would be handled over EDGE. If you had to download a large file directly to the smartphone, it might come into play, but that’s a rather esoteric usage scenario.

The only real application I can think of for the SDA’s Wi-Fi is Voice-over-IP. And to be sure, this is a pretty compelling case. T-Mobile is supposed to be implementing Unlicensed Mobile Access sometime this year, a technology that allows for switching calls between GSM and VoIP networks. Even if this doesn’t come into play, the idea of being able to talk without burning up minutes, or in areas that don’t normally get coverage, is tempting. Such an ability also makes the SDA ideal for use in hospitals or other areas where typical cell phone transmissions might be frowned upon but lower-powered Wi-Fi networks would be acceptable. The SDA could function as both a conventional cell phone and an IP phone, minimizing the hurdles for a comfortable VoIP solution.

On the bright side, there are some positives to the Wi-Fi setup. The device knows how to automatically put the Wi-Fi radio into standby when not transferring data, to save battery life. And it also smoothly handles transitions from EDGE to Wi-Fi and vice versa. By default, the SDA will use Wi-Fi for data if the radio is enabled and a network is available — otherwise, it will run on EDGE.

The SDA is fully equipped out of the box to connect to almost any Bluetooth device, although the most popular option will of course be a Bluetooth headset. For convenience, you can voice-dial any numbers in your speed-dial over a Bluetooth headset or hands-free system, without needing to train the device to recognize you.

Use of the phone as a modem over Bluetooth is fully supported, unlike some other wireless carriers I could mention. It takes a little experience to set up, but once you’ve got it prepped it’s quite easy to get going. I used both my laptop and handheld to test it, and found the results to be quite pleasant.

Oddly, though, the SDA’s EDGE data wasn’t quite what I would have expected. In testing, it consistently performed slower than the Cingular 2125. Not massively slower, but on average about 10 Kbits slower than the other smartphone. I doubt that this is an effect of the network — out here in North Boonies, both T-Mobile and Cingular roam onto the same local network. So I can only attribute the performance drop to different firmware optimizations.

Dialing is handled in the same straightforward manner as other Windows Smartphones. You start off on the “home” screen, and start punching in numbers. It brings up a screen showing what you’ve dialed, as well as Contacts entries which match. You can also type in the name of a contact, or just scroll through the list directly. Once you’ve found who you want to call, the options are self-explanatory, with dedicated buttons for most necessities, as well as soft-menu commands for activating the speakerphone or other options.



To fit standard 3.5mm headphones into the SDA’s 2.5mm jack, you’ll need an adapter, which should be available at any decently equipped electronics store. The SDA comes with a set of cheap earbuds that include an attached microphone, so that you can also use them as a headset. They’re not great quality, so you’ll probably want something else.



T-Mobile only advertises four hours of talk time on the SDA, but the reality is more like eight. While the SDA doesn’t match the fantastic battery life of the Cingular 2125, it comes pretty close. Eight hours of continuous talk time should be enough for all but the most demanding of users. And for those people, there’s always a spare battery.

While the SDA only gets around four hours of continuous Wi-Fi use, it automatically puts the Wi-Fi into a sleep mode when you’re not actively connecting. So you can leave it on for much longer periods without doing the battery much harm.

It may seem strange that you get more time running on cellular than on Wi-Fi, given the fact that Wi-Fi is less power-intensive. But the simple reality is that if you’re using Wi-Fi, you’re also going to have the screen on, which is a big drain, whereas you can use the cellular radio for either voice or data without having the screen active.

On that same principle, don’t expect eight hours of runtime if you’re browsing or sending messages on the SDA either. This would net you around the same four hours as Wi-Fi would.

Overall, I’m pleased. Even in less than optimal signal conditions, the SDA lasts well beyond its rated times, and keeps the juice flowing.



You have the option of either the standard cell phone input — where you continue pressing a given button to select between the various letters it represents — or T9 predictive text input. With the latter, you punch only each button only once, and the system makes an educated guess as to what you’re typing in. It’s not perfect, and there’s an adjustment period associated with it, but it’s better for most things than the older style. T9 is still dependent on what you’re typing being in its word database — if it’s not, you can add words, or select among the possible letter combinations.



The camera in the SDA is very marginal. It’s a better than some of the integrated cameras that you find in handhelds and cell phones, but it’s not even close to good quality. Pictures tend to be blurry, and lighting is an issue in all but the brightest environments. You can see this in photos taken indoors in a well sunlit room. The photos are more shadowy and lacking in detail than they would be in better light. A brightly lit day outdoors produced slightly better photos, but they’re still blurry and distorted. As always, the best advice is to not use the digital zoom, as it only makes the pictures fuzzier.

Cat (indoors, 96 KB)

Front yard (outdoors, 136 KB)



It’s not the most powerful smartphone on the market, but the SDA does have a surprising array of features, all things considered. It’s a jack of all trades, and while it doesn’t master any of them, it does do a fine job on all things phone related, and still provides PIM and computing capabilities good enough for many people. Add to this the option of VoIP, and you could make a strong case for the SDA being one of the most flexible voice-oriented smartphones available.

Although the SDA has a suggested retail price of $300, it can be bought for well under a hundred dollars with new activation. This makes it also one of the cheapest new smartphone devices available, a strong enticement for users looking for light PIM and a solid high end phone.


  • Lightweight
  • Excellent reception
  • Quad-band GSM/EDGE


  • Almost no Storage memory
  • Difficult input

Bottom Line:

Powerful voice-oriented device with some kinks, but overall well done.



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