Skip to main content

T-Mobile Sidekick 4G Review

Our Verdict

Thanks to a best-in class keyboard and fast data speeds, the Sidekick 4G is a great value-priced Android phone for messaging mavens.


  • Excellent keyboard
  • Advanced messaging features
  • Fast data speeds in 4G areas
  • Long battery life
  • Affordable price


  • Non-standard Android interface will confuse some
  • Occasional lag
  • Awkward power button placement
  • Some glitches with Group Chat feature

Old-school Sidekick devotees and jaded Android users take heed: The Sidekick has been reborn, stronger and more advanced than ever. Outfitted with hardware crafted by Samsung and powered by Android 2.2, the Sidekick 4G for T-Mobile has the most advanced messaging features we've seen in a smart phone. For its affordable $99 price, it also boasts a superb keyboard, a front-facing camera, access to T-Mobile's fastest 4G speeds, and plenty of customization options. However, this is definitely not a stock build of Android. Find out if this revamped handset is for you.      


The Sidekick 4G has the familiar rectangular shape of its predecessors along with a "pop-tilt" hinge that flips the phone's screen up and out to reveal a full QWERTY keyboard. When the keyboard is open, the magenta paint job of the screen's back and sturdy hinge is hard to ignore. The same goes for the all-white color of the handset's backside, which contrasts with the front's jet-black shade. Those who want to keep things more conservative can opt for the matte black finish.

Measuring 5 x 2.4 x 0.6 inches and weighing a solid 5.7 ounces, the Sidekick 4G is large but not that heavy. When held in landscape mode, it's wider than the HTC Evo Shift 4G and the T-Mobile G2, both of which also sport physical keyboards. However, this Android handset is lighter than both the Shift 4G (5.8 ounces) and the G2 (6.5 ounces). The Sidekick 4G features a 3.5-inch display with 800 x 480 pixels. While this LCD is smaller than what you'll find on other Android sliders, colors popped and images looked bright and crisp.

Four keys grace the front of the Sidekick 4G on either side of the screen. On the left you'll find Home and Jump buttons, and on the right sit Menu and Back keys along with an optical navigation pad. On the bottom is a headphone jack, the speaker, and buttons for volume and power. The power button, however, is particularly difficult to hit when holding the handset vertically.

Click to enlargeThe Sidekick 4G's top edge features a camera button and a flexible flap covering the micoUSB port. On the back is the phone's 3-megapixel camera, which lacks a flash. It does have a companion front-facing VGA camera on the front, to the left of the Sidekick's screen. Also above the display is the LED notification light, which blinks multiple colors (you can customize this).


The Sidekick 4G's keyboard is just awesome. Not only are the keys well spaced, their rounded rubberized design provides a pleasing click when pressed. You'll be able to fly on this backlit layout. Other welcome touches include two Shift keys and dedicated @, Search, emoticon, and voice action buttons.

Also useful is the default touch keyboard that uses Swype, a text entry method that involves drawing a line from letter to letter. It makes one-handed typing easy but also lets users tap letters by touch. To navigate through menus without touching the screen, there's a dual-action optical navigation pad to the right of the keyboard. Lightly brushing thumbs across it moves the cursor while pressing down makes a selection.

Click to enlarge

User Interface

While the Sidekick 4G has Android 2.2 Froyo under the hood, the interface doesn't resemble your typical Android phone. In a unique twist, the Sidekick 4G's lockout screen displays the time in bold cartoonish letters and is split diagonally down the middle. Pushing up with your finger will launch a predetermined app, while pulling down activates the home screen. There are also useful tabs on the home screen for Apps, Contacts, and Phone.  

Click to enlarge

In an homage to the Danger UI, a side-scrolling Jump menu lists the most recent apps viewed. Tapping the Jump key opens this menu but can also be used to execute shortcut key combos. For instance, pressing Jump then E will launch the e-mail app. Users can assign custom shortcuts to all 26 keyboard letters and 10 number digits. For further customization, there are eight colorful themes from which to choose. Users can also program the phone's LED light to blink in red, blue, or purple for specific notifications such as missed calls and new messages.

Click to enlarge

The Sidekick 4G comes with seven home screens which you can customize using various widgets and app shortcuts. The Feeds and Updates widget can pull in your social-networking feeds, and there's another helpful widget for quickly toggling Wi-Fi, Bluetooth, and more.

Overall, the interface might be a bit confusing for Android purists--especially when you pair that with the unique button options--so you'll have to decide if this handset will work for you.


At its core, the Sidekick 4G is a messaging device on steroids, and this is reflected in its strong text communication features. A Group Texting app handily lets users create groups from contacts using their mobile numbers. You can send texts to an entire group, along with current GPS location, plus all manner of attachments (including pictures, video and audio clips, contacts, and memos). The single messaging app boasts the same abilities. We did run into some glitches, though. Sometimes sending an image through the messaging app failed.

Click to enlarge

To extend the texting experience to PCs, Cloud Text backs up conversations online and provides access to desktop web browsers. The service, however, was not live at the time of this writing. Interestingly, favorite texts can by pinned to the home screen using the Sticky Message app for quick retrieval. This function doesn't seem to work with Group Text, just individual messages.

Keeping in mind the younger demographic for this phone, T-Mobile bundles the DriveSmart feature. Once enabled, it will automatically reply to incoming texts, alerting contacts that the user is driving. DriveSmart can also send messages straight to voicemail. Having the phone detect that it's in a vehicle on its own costs $4.99 a month, which we suspect some parents would be willing to pay.  

Standard e-mail is covered as well, with Gmail and an e-mail app that supports POP and IMAP accounts. The T-Mobile Set Up Wizard app also provides the option to set up Microsoft Exchange accounts for corporate data.

To better keep tabs on your friends, the Sidekick 4G's contact library does its best to merge people's identities across various social networks into one contact page. We found that it worked fairly well, though duplicate contacts with the same name were visible. Still, you can quickly link contacts to their Facebook, Gmail, or Twitter personas, and the phone provides suggestions.

Click to enlarge

Software and Apps

Besides the usual assortment of Android applications, the Sidekick 4G comes with some notable bundled software. This includes Universal Composer, which lets users simultaneously blast updates to Facebook, MySpace, and Twitter. (You can access this feature at any time by long pressing the home button or sliding down the notification drawer.) Allshare allows for media file sharing with DLNA-compliant devices over a network.

Click to enlarge

Entertainment options include the Amazon MP3 app that connects to the company's Cloud Music service for streaming and downloading purchased tracks. Samsung's Media Hub app provides movie and TV show rentals. The T-Mobile TV software and subscription service connects the Sidekick 4G to a library of TV shows, movies, plus live TV from popular channels such as Disney, Fox, and MSNBC. Video quality looked good, and we didn't notice any stuttering even at fullscreen. Media Room is the phone's default music player, which conveniently has Slacker Internet radio built right in.  

Click to enlarge

For GPS navigation, there's the standard offering from Google plus the Telenav application, which provides both basic free and premium navigation. The premium option costs $2.99 per month and includes perks such as real-time traffic alerts, re-routing, speech recognition for addresses, and lane assistance on freeways. Lastly, the pre-installed Qik app enables video chat via the phone's front-facing VGA camera. We made a few Qik calls over Wi-Fi and experienced stuttering video and low volume.


Running a 1-GHz Cortex A8 Hummingbird CPU and with 512MB of internal storage, the Sidekick 4G felt responsive but certainly not as fast as dual-core handsets such as the G2x. Whether moving through menus, opening apps, or scrolling through contacts, the Sidekick 4G exhibited a little lag, which might have something to do with the software overlay.

The handset mustered a Linpack score of 12.6, a benchmark that measures overall system performance. This showing is right on target with the current smart phone average. By comparison, the T-Mobile G2 notched a much faster 28.69 on the same test. On An3DBench, a synthetic graphics benchmark, the Sidekick 4G managed a score of 6,300, which is slightly above the typical Android smart phone. This score beats the T-Mobile G2 (5,933) and the T-Mobile myTouch 4G (6,209).


Equipped with a 3-MP rear-facing camera, the Sidekick 4G captured sharp pictures outdoors. Pictures taken in bright sunshine showcased flowers, fountains, and park benches in rich colors and good detail. Indoor shots under low-light conditions, though, were grainy with washed-out hues. Since the camera lacks a flash, snapshots in dark restaurants and bars are best avoided.

Click to enlarge

In theory, the dedicated camera button is useful. Hitting it while the phone is awake launches the camera, and depressing it halfway activates the autofocus, but it takes a while to lock on. Some may prefer just to tap the screen to snap photos.

Video recorded on the Sidekick 4G looked mediocre, even for a phone. Movies shot at the highest resolution of 720 x 480 looked blocky and unimpressive on a laptop screen. As with other Android phones, users can share both videos and pictures via installed social media apps such as Facebook, Twitter, and YouTube or through e-mail or Bluetooth.

Web Surfing and Connectivity

T-Mobile touts the Sidekick 4G's ability to surf on its HSPA+ 4G network at theoretical peak speeds of 21 Mbps. Other T-Mobile phones, such as the G2x, are limited to 14 Mbps. Using the app, we consistently saw very swift download speeds of 6.1 Mbps in an optimal 4G location. Upload speeds came in at a solid 1.3 Mbps. This beats both the G2 (1.8 to 3.1 Mbps download/1.3 Mbps upload) and the myTouch 4G (1.5 Mbps download/1.3 Mbps upload). The Samsung Galaxy S 4G, another 21 Mbps device, achieved peak download speeds of 5.5 Mbps on our tests.

The Sidekick 4G loaded webpages quickly, too, with the phone loading mobile sites for the New York Times and ESPN in 7.6 and 6.3 seconds respectively. The full desktop version of page took an average of 15.6 seconds to fire up. The Galaxy S 4G performed slightly better, loading mobile sites in 4 to 7 seconds and in a short 12 seconds.

Click to enlarge

The Sidekick 4G also supports mobile hotspot functionality and can supply connectivity for up to five devices. You'll find these tools buried within the Wireless and Network area of the Android settings menu. We'd prefer a dedicated app. You'll pay $15 per month for this feature, which counts against your 5GB monthly data allotment. If you go over that amount, T-Mobile may throttle your speeds.

Call Quality

Click to enlargeDuring our test phone conversations with the Sidekick 4G, callers reported that our voice sounded load and clear. We also appreciated how others sounded through the device's earpiece, which supplied plenty of volume. The rear-mounted speaker also got nice and loud.

Another welcome feature is the Wi-Fi calling app which will make phone calls over wireless networks when a T-Mobile signal isn't in reach. Keep in mind though that chatting over Wi-Fi still counts towards your minutes.

Battery Life

T-Mobile claims that the Sidekick 4G will provide up to 6.5 hours of talk time and 19 days of standby time. On our battery tests, we discovered that the phone's 1,500 mAh battery provides plenty of staying power. It lasted a long 7 hours and 32 minutes before expiring, which is about two hours beyond the typical Android phone.  


Click to enlargeThe Sidekick is back in a big way. For just $99, this well-designed Android phone offers a wealth of messaging features, fast data speeds, and a superior keyboard, making it a great choice for smart phone hipsters on a budget. Android purists who crave a keyboard will likely prefer the T-Mobile G2 for its stock interface and larger display, but that device costs $100 more. If you're not set on T-Mobile, we like the $149 Evo Shift 4G for Sprint for its even faster 4G speeds and 720p video recording. While the interface isn't for everyone, the Sidekick 4G is one of the best smart phones you can get at this price.

Tech Specs

Audio formats supportedAAC, WMA, MP3, MIDI, eAAC+, AAC+
Bluetooth TypeBluetooth 3.0
CPU1 GHz Cortex A8 Hummingbird
Camera Resolution3 MP
Company Website
Display (main)3.5-inch LCD, WVGA 800 x 480
FM RadioYes
Form FactorQWERTY Slider
Internal Memory512MB
Memory Expansion TypemicroSD Card
NetworksGSM; 850 MHz;900 MHz;1800 MHz;1900 MHz;UMTS: Band I (2100);UMTS: Band IV (1700/2100)
Operating SystemAndroid 2.2
Photo formats supportedJPEG
Ports3.5mm headphone, microUSB
Size5 x 2.4 x 0.6 inches
Talk / Standby Time6.5 hours talk/ 19 days standby
Video formats supported3GP, WMV, MPEG-4, H.264, H.263
Weight5.7 ounces