My trusty Samsung SGH-T399 phone began to flake out last week. First it insisted that a number of apps needed to be reinstalled, then some apps lost their data. These sound like memory failures. Within a few days, the phone refused to re-start.
I replaced it with a low-cost Samsung SM-G360T, for $140 from the local T-mobile store. T-mobile calls it a GALAXY CORE Prime™. It’s small (4.5 inch screen), includes LTE, a quad core CPU, 8 GB of memory, 5 megapixel camera, replaceable battery, and a slot for a micro SD card up to 200GB. To keep costs low, Samsung seems to have deleted the magnetic sensor, the automatic screen illumination control, and lighted “back” buttons. I can live without these niceties.
The phone includes Android 5.1.1, which in most respects is an improvement over my old SGH-T399’s Android 4.
I notice on T-Mobile’s website that they’re now discounting this phone for $99. I recommend it, if your needs are similar to mine. At that price, I may buy a second SM-G360T, as a backup phone.
(Originally published December 9, 2015) Last week, without warning, my Samsung SGH-T399 Galaxy Light phone from T-mobile began to download and update its system software to version T399UVUAOH2. Stagefright Detector now reports that my phone is no longer vulnerable to the Stagefright virus.
My phone’s About screen reports that its Android operating system remains at version 4.2.2 (Jelly Bean), but its kernel is now dated August 25, 2015 (Korean standard time).
Tip: If your Android phone is vulnerable to the Stagefright virus, you can reduce (but not eliminate) its vulnerability by, within the Messaging app, turning off the Auto retrieve setting. The Stagefright virus arrives within an SMS (short message service) multimedia message, so if your phone is vulnerable, you do not want to download these messages.
Update, February 27, 2016: T-Mobile again updated my T-399 phone. It still reports Android version 4.2.2, but now reports baseband version T399UVUAPA1 and is dated January 4th, 2016, 20:32, Korean Standard Time. According to T-Mobile’s note that accompanied the update, it improves voice over LTE (VoLTE) and unspecified security features.
Last week, my Samsung Galaxy Light SGH-T399 phone with Android 4.2.2 stopped responding to orientation changes. When I rotated the phone from vertical (“portrait”) to horizontal (“landscape”), the display no longer rotated accordingly. In vain I clicked on the Screen rotation button.
I feared that I’d physically broken the orientation sensor when I dropped the phone the previous day. I loaded a rotation app, but found that it was a pain to use. Eventually I discovered (thanks, Google) that by typing an odd sequence of keys, I could peek beneath the operating system and directly examine the data streams from the sensors. When I did this, the phone’s screen rotation function returned.
Run the phone app, which displays the dial screen.
In sequence, press the *#0*# buttons on the dial screen.
A hardware test screen with 14 buttons should appear.
Tap the Sensor button
You’ll see the numeric outputs of the Accelerometer, Proximity, and Magnetic sensors
Press the IMAGE TEST and Graph buttons for the Accelerometer. The displays should respond to movement of the phone.
I discovered a method of freeing storage space on my Samsung SGH-T399 Android phone. Podcasts had stopped streaming, probably because the phone had run out of free storage space for caching. How could I create free storage space? I learned that the hidden /mnt/sdcard/.face folder had grown to 2.65 gigabytes and contained 67,000 files(!). I gambled that the facial recognition files contained there were nonessential.
I deleted the /mnt/sdcard/.face folder, then created a new empty /mnt/sdcard/.face folder. Suddenly the phone had 2.65 GB of free storage. Yesssss!
I used a terrific Android app, ES File Explorer, to discover this bloated folder, delete it, and create a new empty one. Its SD Card Analyst tool displays folders sorted in descending order by size. The .face folder was at the top of the list.
Note that the folder named sdcard isn’t actually the physical sdcard. For some reason, Samsung’s Android file system calls this phone’s internal storage folder /mnt/sdcard. The physical sdcard is named /mnt/extSdCard.
My trusty Samsung SGH-T679 phone stopped accepting touch input last Friday. I replaced it with a Samsung Galaxy Light 4G LTE SGH-T399 for T-Mobile phone. Like the T-679, it’s small and lightweight, but it’s much more powerful. T-Mobile is discounting them for $99, unsubsidized. At this low price, I didn’t expect such a great phone.
The phone’s performance is amazing. Apparently it has a quad-core CPU with separate GPU, 1 gigabyte of RAM, and 8 gigabytes of storage. It includes a slot for an SD card. The phone is fast and smooth. Its operating system is Android 4.2.2, which includes many refinements. Its email client — in fact, everything — allows more tweaking than my old SGH-T679 did.
The radios include LTE (true 4G), 802.11n WiFi, Bluetooth 4.0, and NFC (near field communication). Ookla SpeedTest reported 14 Mbps download speed while connected via LTE with a signal strength of about -100 dBm. I’ve seen download speeds of 29 Mbps via LTE with stronger signals.
While listening to a podcast on my Samsung mobile phone via the Tunein app, a pop-up announced, “Charging paused. Battery temperature too low or too high.” The pop-up remained on screen until I unplugged the charger. The battery had only about a 6% charge, so as soon as I unplugged the charger, another pop-up warned that the battery needed to be charged. Catch 22. Room temperature was probably about 77 degrees Fahrenheit.
I grabbed a cold pack from the freezer and rested the phone on its icy carcass. The over-temperature warnings ceased while I simultaneously listened to the podcast and charged the phone’s battery.
Decades ago, I helped develop military radio communication hardware. The products needed to pass environmental tests for vibration, shock, high and low ambient temperatures, and humidity — while under continuous full-load conditions. We invested many hours in heat management.
My mobile phone is clearly incapable of passing such tests. It’s intended for intermittent use — what’s known as low duty cycle usage. I’d guess that my phone can handle about a 10 to 15 percent duty cycle at full output.
This is probably as good as we can expect from consumer-grade products. We just need to have frigid cold packs ready if we want more.
My phone: Samsung SGH-T679. T-Mobile Insight II 4G.