Cellphone Hacks

528 Articles

Nokia 5110 Gets Android Stowaway And A Keyboard

July 21, 2022 by 11 Comments

Even though Nokia is largely an afterthought in the phone market now, there was a time when their products represented the state-of-the-art in mobile devices. Some of the their handsets even featured slide-out keyboards and the ability to sent emails; largely unheard of for a device from the late 90s. [befinitiv] was a kid back then and couldn’t afford one of these revolutionary devices, so he built his own modern version that still looks and feels like the original.

To do this he borrowed the case and structure of a Nokia 5110 phone, but modified it to hold a small Android device in the old battery compartment along with a tiny Bluetooth keyboard (which was also built from scratch by [befinitiv]) that connects to the Android phone to mimic the old slide-out style. This isn’t just a case mod, though. He also reverse-engineered the original PCB of the phone and included a Bluetooth module there as well, which allows the phone’s screen and keypad to work mostly as originally intended.

This project goes pretty far to scratch the 90s phone nostalgia itch while still being largely usable as a real phone in the modern world. Assuming you aren’t too hung up on the literal phone aspect, the Notkia project is also an impressive effort to bring new life to these old handsets.

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On the left side, there's a smartphone. On the right side, there's a hairdryer turned on. On the smartphone screen, you can see the working end of the hairdryer shown, as well as a jet of air coming out of that end. In the background, there's an LCD screen showing a noise pattern.

Observe Airflow Using Smartphone And Background-Oriented Schlieren

July 17, 2022 by 22 Comments

Multiple people have recently shared this exciting demonstration (nitter) with us – visualizing airflow using a smartphone, called ‘background-oriented schlieren’. On a hot summer day, you might see waves in the air – caused by air changing density as it warms up, and therefore refracting the light differently. Schlieren photography is an general set of techniques for visualizing fluid flow, but of course, it can also be applied to airflow. In this case, using some clever optical recognition tricks, this schlieren method lets you visualize flow of air using only your Android smartphone’s high resolution camera and a known-pattern printed background! Continue reading “Observe Airflow Using Smartphone And Background-Oriented Schlieren” →

Automatic Turntable Makes Photogrammetry A Cinch

April 28, 2022 by 9 Comments

Photogrammetry is a great way to produce accurate 3D models of real objects. A turntable is often a common tool used in this work as it helps image an object from all angles. [Peter Lin] wanted a way to run the photogrammetry process with minimal human intervention, and set about building an automated turntable setup.

The build relies on a smartphone to take images of the physical object. The phone is triggered to take photos by an ESP8266, which fires the shutter via the phone’s audio socket. The microcontroller then turns the turntable on for a short period of time after each shot, rotating it by a set angle.

The build still requires objects to be repositioned in various orientations on the turntable now and then, in order to capture the top and bottom areas that would otherwise be obscured. However, the grunt work of taking the photos and rotating the objects is now entirely automated.

It’s a useful build for anyone that finds themselves regularly imaging objects to create 3D models. The results of [Peter]’s rig look great, and as a bonus come with life-like textures ready to go. We’ve seen some other great photogrammetry builds before, too. Video after the break.

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Monitor Space Weather And The Atmosphere With Your Cellphone!

April 4, 2022 by 9 Comments

Above our heads, the atmosphere is a complex and unpredictable soup of gasses and charged particles subject to the influence of whatever the Sun throws at it. Attempting to understand it is not for the faint-hearted, so it has for centuries been the object of considerable research. A new project from the European Space Agency and ETH Zurich gives the general public the chance to participate in that research in a small way, by crowdsourcing atmospheric data gathering to a mobile phone app. How might a mobile phone observe the atmosphere? The answer lies in their global positioning receivers, which can track minute differences in the received signals caused by atmospheric conditions. By gathering as much of this data as possible, the ESA scientists will gain valuable insights into atmospheric conditions as they change across the globe.

The app requires an Android phone equipped with a dual frequency satnav receiver, and having been duly installed on the trusty Hackaday Motorola it in turn started picking up all the different constellations of satellites. The instructions are to leave it somewhere such as a windowsill with an unobstructed view of the sky and move it as little as possible, to which we’d add clicking the “Log in background” button and connectign a charger. There’s a promise that uploaders can win prizes, so aside from contributing to scientific discovery there might be an unexpected benefit. More details on the app can be found here, meanwhile many readers will know that this isn’t the only crowdsourced atmospheric data gathering effort.

Galaxy Users Accuse Samsung Of Throttling Performance And Benchmark Rigging

March 10, 2022 by 24 Comments

A lot of Samsung Galaxy users think that Samsung has been throttling smartphone performance, so much so that they don’t live up to their published specifications. At issue is the game optimizing service (GOS) which is intended to throttle the CPU while playing games to prevent overheating. S22 owners have recently discovered that it’s not only games that are throttled, but there’s a list of over 10,000 apps which are subject to GOS control, and there is no way to disable it.

What they’re really upset over is the fact that popular benchmarking apps are not subject to GOS throttling — something that’s hard to see as anything but a blatant attempt to game the system. In fact, this past weekend the folks at Geekbench banned four generations of Samsung Galaxy phones (S10, S20, S21, S22) for benchmark manipulation.

Admittedly, thermal management is critical on today’s incredibly powerful handheld devices, and the concept of throttling is an accepted solution in the industry. But people are upset at the opaqueness and lack of control of GOS, not to mention cherry picking apps in order to excel at benchmarks. Furthermore Samsung has removed their vapor chamber cooling system from recent models. This makes GOS even more important and looks like a cost-savings measure that may have backfired. Currently there’s a petition with the government claiming false advertising, and users are actively pursuing a lawsuit against Samsung.

First Hacks: The Brand New Nokia 5G Gateway Router

December 27, 2021 by 28 Comments

Aside from being the focus of a series of bizarre conspiracy theories, 5G cellular networks offer the promise of ultra-fast Internet access anywhere within their range. To that end there are a new breed of devices designed to provide home broadband using 5G as a backhaul. It’s one of these, a Nokia Fastmile, that [Eddie Zhang] received, and he’s found it to be an interesting teardown and investigation. Spoiler: it runs Android and has exploitable bugs.

A privilege escalation bug in the web administration tool led to gaining the ability to export and modify configuration files, but sadly though a telnet prompt can be opened it’s not much use without the password. Uncovering some blocked-off ports on the base of the unit revealed a USB-C port, which was found to connect to an Android device. Via ADB a shell could be opened on Android, but on further  investigation it was found that the Fastmile is not a single device but two separate ones. Inside is a PCB with an Android 5G phone to handle the connection, and another with a completely separate home router.

With access to the Android side and a login prompt on the router side that was as far as he was prepared to go without risking bricking his Fastmile. It only remained to do a teardown, which reveals the separate PCBs with their own heatsinks, and an impressive antenna array. Perhaps these devices will in time become as ubiquitous as old routers, and we’ll see them fully laid bare.

It’s a shame that we’ve had to write more about the conspiracy theories surrounding 5G than real 5G devices, but maybe we’ll see more teardowns like this one to make up for it.

Inspecting a SIM card via MTM

Diving The Depths Of Ma Bell

December 27, 2021 by 13 Comments

The modern smartphone is a marvel of sensors, radios, inputs, outputs, and processing power. In particular, some of those radios, such as WiFi and cellular, have grown fiendishly complex over the years. Even when that complexity is compressed down for the user into the one-dimensional space of the signal strength bars at the top of your phone. So when [David Burgess] was asked to look at some cellphone records of text messages and figure out where some of the more mysterious messages were coming from, it led him down a rabbit hole into the dark arts behind the glowing phone screen.

The number in question was 1111340002, sent by a phone connected to AT&T at the time, and was crucial for a legal case around distracted driving. [David’s] tools in his investigation were YateBTS (a cellular network simulator), SimTrace2 (pictured above), and old reliable Wireshark. Since the number isn’t a specific phone number and is not reachable from the public phone network, it must be a unique number inside AT&T processed by one particular AT&T SMSC (Short Message service center). The SMSC in question is in Atlanta and isn’t a typical texting center, so it must have some particular purpose. The message’s payload is raw binary rather than text, and [David] has done a pretty good job of decoding the majority of the format.

The most exciting revelation in this journey is that the phone (in the traditional sense) does not send this message. The processor on the phone does not know this message and executes no code to send it. Instead, the SIM card itself sends it. The SIM card is connected directly to the baseband processor on the phone, and the baseband polls the sim every so often, asking for any commands. One of those commands is an SMS (though many other commands have worrying consequences).

The SMS that [David] was chasing is triggered whenever a SIM detects a new IMEI, and the message lets the network know what about the previous and current IMEI. However, in the case of this message, it was unlikely that the SIM changed phones, so what happened? After some additional lab work and the deposition of an AT&T employee, [David] showed that a baseband firmware update would also trigger this SMS.

It’s a fascinating journey into the fragmented world of a smartphone’s minds and [David] does a fantastic job on the writeup. If you’re interested in sniffing wireless accessories, you will enjoy this soundbar’s wireless protocol laid bare.