Specs summary


The Sidekick 4G's screen is 3.5 inches with 480 x 800 pixels resolution.


There is a ARM Cortex A8 1 GHz processor (CPU).


The phone runs on the Android 2.2 Froyo operating system (OS).

3+ MP

You can take photos or capture video with the phone's onboard 3+ megapixel camera.

There is also a secondary front facing camera useful for video chat and self portraits.

135 MB

Internal memory is 135 MB. An external, MicroSD (up to 32 GB) expansion slot is available for increased storage capacity.


The phone is powered by a Lithium-Ion (Li-Ion), 1500 mAh battery. Samsung's performance ratings are 19 days standby time, 390 minutes (2G).

It carries the name of a heralded messaging device, some might even say "the best" messaging phone, yet it runs a modern, internet-loving smartphone operating system.

- Dan Seifert , MobileBurn 

Reviews summary

Based on 15 reviews

The latest iteration of the Sidekick runs on the new, 4G network and is powered by Android 2.2. Retaining its unique sliding approach, a fast horizontal spring-slide that leaves the screen at a slight inclined angle, the Sidekick 4G offers a 3.5 inch touchscreen generating an impressive 480 x 800 pixels. Of course, you also get a full and spacious QWERTY keyboard.

Packed inside this now iconic phone you'll find a 3MP camera, video record, and a second camera for video calling. Add an MP3 player, native YouTube support, full internet browser with Facebook and Twitter support, and you have a fun slider packed with features people want.

Show more

But this latest version of the Sidekick offers some surprising additional features, such as tethering and DLNA support, putting it squarely at the top of many customer wish lists.

Rounding out the feature list you'll find GPS, Bluetooth 3.0, WiFi, expandable memory up to 32GB via microSD, and the always welcome 3.5mm headset jack.

To this writer anyway, it looks like the Sidekick has grown up gracefully, and continues to be relevant as a smartphone option full of fun and productive features that will keep any user busy and fulfilled for some time.

Reviews (7.9/10 Avg. rating)


It's solid, stable, feature-packed and incredibly stylish for the price

from Engadget

The growing Android empire has legions of slatephones big and small, and a growing stable of physical QWERTY devices led by the likes of HTC's G2 / Desire Z, Samsung's Epic 4G, and of course the Motorola Droid 2. All of those play at the higher end of the market, though, where folks can afford phones built from metal or filled with organic LEDs, while this perfectly passable Sidekick 4G rings up at just $100 on contract. It's solid, stable, feature-packed and incredibly stylish for the price, and we don't think it's an exaggeration to say it might single-handedly raise the bar for what a mi... Full review


A good choice for primarily messaging-oriented entry level customers, and slightly more advanced users alike

from Brighthand

Looked at solely on its own merits, the T-Mobile Sidekick 4G is a very solid device. It's got nice build quality, a great keyboard, fast performance, and an ergonomically comfortable design for messaging. However, it's when you look at the device in the context of its $100 suggested retail price that it becomes a hit. Samsung and T-Mobile have delivered a solidly mid-range experience, on a solidly low-end budget. The result is a phone which I don't hesitate to recommend as being one of the best entry-level smartphones I've used. While it may not match the flash and bang features of the high... Full review


Excellent for social networkers or first-time smartphone owners

from Macworld
The Sidekick won’t appeal to everybody: it’s no dual-core, large screen, enterprise-heavy super phone. But then again, that’s not really what the Sidekick brand is all about. It’s not really meant to be used in the boardroom. The Sidekick was designed for social networkers, first-time smartphone owners and people who really appreciate a good QWERTY keyboard. I think the Sidekick succeeds at what it sets out to do and more. For $100, you get a 4G phone with some fantastic messaging capabilities and a fun but useful design... Full review

A solid Android device with an amazing keyboard, fast Internet speeds, and great battery life

from IntoMobile
As an old Sidekick user, I can confidently say that this will definitely appeal to Sidekick users from days of yore, and it might even steal some of the kids who flocked over to BlackBerry when Sidekicks started slipping and taking a back seat to everything else. Even though it’s made by a new manufacturer with a new OS and more powerful guts, it’s unmistakably a Sidekick from a mile away... Full review
Laptop Magazine

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

from Laptop Magazine

The 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 c... Full review


Great keyboard, snappy response, and good battery life

from MobileBurn

Thankfully, the Sidekick 4G holds true to most of the qualities of its predecessors. The must-have QWERTY keyboard is present and accounted for, and there are plenty of tweaks throughout the operating system designed to focus the user's attention on messaging. Of course, since it is a full-fledged Android device underneath its messaging skin, the Sidekick 4G benefits from a great browser and a very strong app ecosystem.

The Sidekick 4G turns out a great user experience and was a real pleasure to use throughout our review period. While it is not the most svelte device we have ever... Full review

Phone Scoop

It offers an abundance of messaging capabilities and a great keyboard

from Phone Scoop

The Sidekick 4G is clearly not Samsung's best effort, nor is it Samsung's worst. It has a few nifty innovations, and one of the best keyboards I've used in a long time. It does well at the basics, such as call performance and battery life, though my review unit displayed a propensity for signal inconsistency.

Messaging options are numerous, and include Group Text and Cloud Text for the first time. Surely the target demographic for the Sidekick 4G will enjoy those. The camera performs merely OK for this class of device, and the media options are better than normal.

My... Full review

Android Community

The Sidekick 4G truly sets apart from the rest of the Android pack

from Android Community
If you’re used to our most modern review series here on Android Community, you’ll notice a lack of a few things, most notably benchmarks comparing this phone to its compatriots. Why would I skip such a series of tests? Because they don’t matter. What Samsung and T-Mobile have done here with Google and the Sidekick brand is to finally, truly set an Android device apart from the rest of the pack. Processor speeds and rooting ability be forgotten – this is it. This is a brand new direction for smartphone creators to take... Full review

Fast download speeds, great text entry system and a processor that can handle all tasks

from GigaOM

For the text messaging teen who wants a smartphone experience, the Sidekick 4G is a must-see. I raised concerns with the T-Mobile folks about the added expense of a data plan, but they pointed out that the $10 monthly plan that includes 200 MB of data qualifies the Sidekick 4G for the $99 cost. That could be enough data for some, provided the kids use Wi-Fi where available.

Both my children are sad to see the Sidekick 4G review unit go back, which definitely says something. And I understand the appeal, since both are current smartphone users who send thousands of text messages pe... Full review


This modernized Sidekick will undoubtedly keep up with the demanding needs of the no talk and all messaging personalities

from PhoneArena

Believed at one point to be utterly annihilated from existence, which blackened its reputation somewhat with the mini meltdown that occurred back in late 2009, the lovable Sidekick line is alive and beating once again. Still placing its emphasis on the messaging and social networking oriented aspects, the reincarnated T-Mobile Sidekick 4G brings back the popular line with its new manufacturer in Samsung and involvement with the Android platform – as opposed to the forgettable Danger OS which previously powered the Sidekick. Naturally, the handset has been given a modernized ma... Full review

Darn, there are no reviews yet for this phone.

Prices (Where to Buy)

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Sidekick 4G Unboxing & Hands On


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Full Specs

Release date May 31, 2011
Regions available USA
850/900/1800/1900 MHz
1700/2100 MHz
SIM Card Yes
Dual SIM No
Operating System Android 2.2 Froyo

Compare Android Smartphones

Processor ARM Cortex A8 1 GHz
Internal Flash Memory
135 MB
RAM 512 MB
Digital compass No
FlightMode Yes
Hearing Aid Compatible Yes
Noise Cancellation Yes
SAR Head: 0.34 W/kg
Body: 0.96 W/kg
Languages English, French, Spanish
Manufacturer Warranty 1 Year
Accessories Included AC Charger, Data Cable, Manual, Standard Battery
Power & Battery
Type Lithium-Ion (Li-Ion), 1500 mAh
Removable Battery Yes
Wireless Charging Unknown
Fast Charging No
Video Playback Time Unknown
Wi-Fi Surfing Time Unknown
3G Surfing Time Unknown
4G Surfing Time Unknown
Talk Time Up to:
390 minutes (2G)
Standby Time Up to: 19 days
Physical Characteristics
Design Type Slider
Multi-Use Smart Phone / PDA Yes
Material Unknown
Colors Pink & Black, White & Black
Dimensions [H x W x D] 12.7 x 6.1 x 1.5 cm
(5 x 2.4 x 0.6 in)
Weight 162 grams
(5.7 ounces)
Water Resistant / Waterproof Unknown
Rugged Design No
IP Rating No
Antenna Type Internal
Changeable Faceplates No
Display / Screen
Type Color
Technology LCD (TFT)
Colors Unknown
Resolution 480 x 800 pixels
Pixel Density Unknown
Size 3.5 inches
3D No
Secondary Display No
Sensors Ambient Light, Proximity, Motion / Accelerometer
Graphics Yes
Themes Yes
Backlit Illumination Yes
Zoom / Magnification Yes
Screen Orientation Lock Unknown
Multi Touch Unknown
Fingerprint-Resistant Coating Unknown
Additional Display Features Capacitive
Input / Navigation
Sleep / Wake Key Unknown
Home Key Unknown
Mute Key Unknown
Input Type QWERTY, Touchscreen
Navigation Type Touchscreen
Predictive Text Entry Yes
Physical Keyboard Unknown
Voicemail Key Yes
Any Key Answer No
Voice Commands No
Keypad / Screen Lock No
External Volume Control Yes
External Media Playback Controls No
Fingerprint Sensor No
Call Management
Wi-Fi Calling Unknown
Voice over LTE (VoLTE) Unknown
Contact List Capacity Depends on system memory
Multiple Numbers Per Contact Email address, Other fields
Contact Groups Unknown
Auto Answer Yes
Voice Activated Dialing Yes
Photo Caller ID Yes
Web / Email / Messaging
Web Browsing Type HTML
Browser Google Android
Javascript Yes
Flash Yes
Email Yes
Email Protocols POP3, IMAP, SMTP
Additional Email Features No
Messaging Services SMS, MMS, IM (Google Talk)
Push-to-talk (PTT) No
USB Micro-USB 2.0
USB OTG Support No
Infrared No
Bluetooth 2.1
Bluetooth Profiles A2DP
WiFi 802.11 b/g/n
WiFi Encryption WPA/WPA2
Mobile Hotspot No
Expansion Slots Yes
Expansion Slots Info MicroSD (up to 32 GB)
PC Synchronization Yes
TV-out Yes
DLNA Support Yes
UMA Support No
Data Tethering Compatibility Yes
Java Applications Yes
Brew Applications No
ECML / Digital Wallet No
PictBridge No
Main Camera  
Aperture Unknown
Resolution 3+ megapixels
Dual Lens No
Zoom Yes
Flash No
Additional Rear Camera Info Auto focus, Geotagging, Panorama, White balance
Video Recording Formats 3GP / 3GPP, MPEG-4
Video Recording Parameters 720 x 480 pixels
Front Camera  
Zoom Unknown
Additional Front Camera Info VGA
Video Recording Parameters
Audio / Video
Audio Playback Yes
Audio Formats MP3, AAC+, AAC, WAV
Radio No
Video Playback Yes
Video Playback Formats 3G2 / 3GPP2, H.264 / AVC, MPEG-4
Mobile TV No
Streaming Video Yes
External Speakers No
Headset Jack 3.5mm
Custom Ringtones No
Vibration Alert Yes
Downloadable Ringtones Yes
Ringtone Composer No
Ringer ID Yes
Haptic Feedback Vibration Yes
Speakerphone Yes
To-Do / Task List Yes
Calendar Yes
World Clock Yes
Alarm Yes
Stopwatch Yes
Timer Yes
Calculator Yes
Currency Converter Unknown
Weather Yes
Stocks No
Maps Yes
Notepad No
Voice Memos / Recorder Yes
Games Downloadable
Apps Downloadable, Pre-installed
Included Software / Apps No
Additional Comments Other Names (AKA): T-Mobile Sidekick 4G, Samsung T839

2Gb microSD card included
Related Links Sidekick 4G Manual (PDF)
Sidekick 4G Reviews
Where to buy Sidekick 4G
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