My existing Samsung Galaxy S5 (2015) is now five years old and it's showing its age. Plus it's in a time warp, updatewise. Now is the time to replace it.
Timeline of my pocket computers:
|To be determined||2020-02-07||(New)|
|Samsung Galaxy S5||2015-04-15||Works, elderly, no kernel updates|
|Samsung Galaxy S3||2012-10-23||No upgrade to CM-12 (Lollipop)|
|Motorola Droid 3||2011-11-23||Bit rot (memory failure)|
| HTC G1 |
|2009-03-30||Insufficient memory for CM-7 (Gingerbread)|
This time around, my selection criteria for the new pocket computer are (in approximate order of importance):
The machine must have a CyanogenMod version available. I'm not going
to deal with vendor hacks of doubtful security, nor with usage restrictions
that I can't bypass. The legal issues with the name
are discussed later.
Unless something really nasty turns up, I'm going to insist on the possibiity of kernel updates. The Galaxy S5 is on kernel 3.1.7 (3.1.x was maintained 2011-10-xx to 2012-01-xx), while 5.5.1 (on my laptop Xena) is the latest (2020-01-26). This is not acceptable. My criterion is going to be that an image is available with a kernel no more than 6 months old, which at this date would be kernel version 5.2.x. Update: the modern paradigm for cellphones is that they pick the most recent kernel with long term support (LTS), and never change the underlying version. But with CyanogenMod, LTS releases with relatively recently backported security patches are available, and that's what I'm going to have to accept.
The carrier continues to be T-Mobile (GSM) in the USA. A phone that could do both GSM and CDMA would be rated highly, but of these two, GSM is more important to me, for use when travelling. GSM is widely available both abroad and in the USA. 4G LTE is widely available in urban areas, plus some rural areas, and at present all credible phones can handle it. 5G is appearing gradually, and I would probably choose a phone that can do 5G if it meets my other criteria, but most of these criteria take priority over 5G, so I might well sacrifice 5G capability.
The pocket computer must be unlocked, referring to the ability to flash
arbitrary software (vs. sabotaging operation with other carriers). I will
be putting non-vendor software on it, and I've had unpleasant prior
jailbreaking locked phones.
I view HTML content a lot. The phone must have a nice display. It looks like modern phones are 130mm diagonal and 1920x1080px, which is total overkill.
At times I use the hand computer outdoors in direct sunlight, particularly for map navigation. It is quite important that the display be readable in that situation, even though its color and contrast may be degraded from its performance in artificial light. A transflective display (color) would be rated highly if available; so would flight capability of pigs. The OLED display on the Galaxy S5 has been satisfactory but not wonderful, in sunlight.
Starting with the Galaxy S3 I switched to an on-screen keyboard, and this choice has worked out, so once again I will not look for the physical keyboard that the G1 and the Droid 3 had. Is there any phone these days that has a physical keyboard? In the past I've used successfully a folding Bluetooth keyboard for extensive data entry, and recently I wrote a HTML document of about 90K words (average 6 bytes/word counting separating blanks) using a flat text editor and the on-screen keyboard.
I would like fairly long battery life, but assessing the battery life before purchase is hard, and published data often is on tests that don't match my (or any live user's) usage pattern, so the life actually achieved is substantially less than the product hype. Formerly I insisted on a field-replaceable battery; however, with the Galaxy S5 I've found that an external power bank has worked well for keeping me entertained on a long flight. Also, batteries last a lot longer these days than in 2008 when I had the Droid-3; in five years the S5's battery has lost about one third of its capacity. In the unlikely event that the new phone also lasts five years, I'm willing to do a professional battery replacement.
The Galaxy S5 has a slot for a user-provided SD card; however, the Android permission system made it very hard for me to put anything useful on this card. I would still like a card slot on the new pocket computer.
Like most people, I have converted to using the pocket computer for photography rather than a dedicated camera, and I would like a decent camera. The F number, sensor pixel count, and focal length (physical size) are the key dimensions here. Optical zoom would be very nice but I'm not likely to get this. In product reviews the author's nitpicks usually refer to issues, like overall image brightness or color balance, that are controlled by the vendor-provided camera program and they aren't judging the camera itself.
Here is a list of features that are important, and that every modern cellphone is expected to have.
Wired headphones and Bluetooth A2DP are required for music listening. Every phone should have both. A 3.5mm stereo jack is preferred over a proprietary jobbie like on the HTC Dream.
I rely on the pocket computer for navigation and mapping. It must have a GPS receiver for this activity. All modern phones have GPS.
Photography with a rear-facing camera. Massive resolution is not needed; it's impossible for a cellphone to have optics to match the sensors that go into cellphones these days. Auto focus is important for jobs like reading barcodes, which is one of my major uses of the rear-facing camera. LED flash is a nice addition.
USB connection to the host computer, including Android debugging. All Android phones have this. File transfer without unmounting the SD card is desirable, but this is an OS issue.
Charges from a generic micro-USB or mini-USB connector, not a vendor-specific charger like Nokia's old 1.5mm cylinder connector. This is a Chinese commerce department requirement and even modern Nokia phones charge through USB. Today's phones have a USB type C connector and can negotiate high voltage with a cooperating charger, translating into fast charging.
Here is a laundry list of features which would be nice but are not deal-breakers if absent. They are ordered by importance.
Water and rain resistance. The Galaxy S5 has IP67 (Intrusion Protection): essentially no ingress of fingers, tools or dust, and immersion 1 meter under (non-salt) water for 30 minutes. While flagship phones tend to make the IP rating a point of competition, not all phones are water resistant. I hope that the phone I get will have a good IP rating like the Galaxy S5.
Adjusts the screen brightness according to the ambient light level. The Galaxy S5 does this very nicely, and it saves battery while keeping the display readable as lighting changes.
Video chat with a front-facing camera.
A lot of pocket computer activities depend more on operating system support than on hardware components. However, the point here is to pick the hardware. But we need to keep aware whether the operating system uses that hardware effectively.
First, what's happened to CyanogenMod? Cyanogen (the lead developer),
after a period of close relation with Samsung, made a deal with whoever makes
the One-Plus to use CyanogenMod as the standard distro on their phones. But
something bad happened, and they got divorced, with One-Plus retaining the
right to CyanogenMod's name. In the mad scramble after that collapse, Cyanogen
and the development team came up with
article about it). Not the name I would
have chosen: wouldn't WebScorpion or Boomslang be a better name for a killer OS
image? Anyway, that's not really my business.
In forum posts the acronym
LOS is sometimes used for LineageOS.
There are 126 supported devices (currently in early 2020) plus 143
devices with unmaintained (
discontinued) images that could even so
be downloaded. I've got to automate the process of detecting those with
The mapping from versions to maintenance date ranges may be found in the Wikipedia article Linux kernel version history. Here is the distribution of kernel versions.
It appears that the paradigm in cellphone kernels is to pick a LTS (long term support) release and never change it, whereas desktop distros update their kernels on a regular schedule plus upon security bugfix releases. My hope of finding a phone with a more desktop-like kernel update policy does not seem to be working out.
What are the currently known phones with the two most recent kernels,
only 4 years old, compared to 8 years for my Samsung Galaxy S5? The
dates are when Greg Kroah-Hartman announced the release of these particular LTS
updates; note that these are relatively recent. Quickly scanning the
changelogs, I notice that contemporaneously relevant issues were being
addressed, i.e. backported, such as the Spectre branch prediction side channel
How much work should I put into adding to the ability of my unpacker program to determine the kernel versions of the 72 unknown phones? It looks like all of the vendors with recent kernels have newer models with unknown kernel versions. The major vendors are not represented (i.e. are represented with older models and older kernels). Probably there has been a change in the manner of packing the boot image, which my program does not know about. But how much is the selection still going to be driven by recency of the underlying kernel (version number) versus LTS and inclusion of backported patches? I think it's prudent to determine the kernel version numbers (and LTS release dates) of more major vendors, and specifically to find out why their offerings were not unpacked by my program.
Here's a list of targeted models, with these selection criteria: picking the most recent (having CyanogenMod support) of each vendor's product line; excluding vendors that I know little about or have had a bad experience with or which are blacklisted for security violations in other product lines. They are sorted by attractiveness with a very limited look at specs and availability. None is the vendor's latest product; it takes time to get CyanogenMod running on a new phone. Chassis names are capitalized (if words) whereas download dirnames and basenames are lower case.
Obviously only the first three are viable, and the Motorola River (Moto G7) has obvious advantages over the others. (One of CyanogenMod's missions is to bring recent AOSP images to older phones, no longer supported by their vendors or carriers, like the ones I'm excluding at this step.) The way forward is clear: do the research to unpack the images for these, and determine the kernel version. Prepare a comparison table of features. Assuming that the River wins on features, find review articles and look for gotcha's that I'll need to work around.
Steps in discovering version numbers:
The image file is still a zip file.
unzip -lv $chassis-signed.zip to list contents, which are:
payload.bin is not in any recognized format, and
does not reveal uncompressed structure that could be pulled apart.
How to Extract Android OTA Payload.bin File using Payload Dumper
by Dhanajay (2019-10-17 in thecustomdroid). Use Payload Dumper by
Gregory Montoir, written in Python, works on Linux. Link from
payload_dumper.zip. This is actually HTML; follow the download
link on the page, and read README.md once you get it unzipped.
It is not a simple command line tool like unzip is; the unpacked result
ends up in a directory
output in the same dir that the script
is in. You end up with a boot.img file on which you can run abootimg.
Most of this information is from the
LineageOS Devices List.
feature column, numbers in parens refer to notes at the end
indicating other sources of information.
|Model (text)||Moto G7||Xperia XA2||G3|
|Carrier||Verizon AT&T T-Mobile etc||Verizon (5) AT&T T-Mobile etc||T-Mobile|
|Product Page||(Moto G7)||(Xperia XA2)||(LG G3)|
|Price on Amazon (1)||$200 (AZ)||$315 (OV)||$230 (OV)|
|Chipset||Snapdragon 632||Snapdragon 630||Snapdragon 801|
|CPU||A53 1.8GHz x8 core||A53 2.2GHz x8 core||Krait 400 2.5GHz x4 core|
|GPU||Adreno 506||Adreno 508||Adreno 330|
|SD Card||Up to 256Gb||Up to 256Gb||Up to 256Gb|
|Cell Family||GSM GPRS HSPA LTE (5)|
|Screen||158mm 1080x2270px IPS||132mm 1080x1920px IPS||140mm 2560x1440px IPS|
|Wi-Fi||802.11 abgn,ac||802.11 abgn (4)||802.11 abgn,ac|
|Other (6)||Finger Accel Compass Gyro Prox HallEf Light GPS FM-Radio (no NFC)||Finger Accel Compass Gyro Prox NFC GPS FM-Radio||Accel Compass Gyro Prox NFC|
|Rear Camera (+flash) (3)||12Mpx, f/1.8||23Mpx, f/2.0, 84° wide angle||13Mpx|
|Front Camera (no flash) (3)||8Mpx||8Mpx, f/2.4, 120° wide angle||2.1Mpx, f/2.0|
|Other Camera||Depth sensor, 5Mpx, flash|
|Battery||LiIon 3.0Ah non-rem||LiIon 3.3Ah non-rem||LiIon 3.0Ah remov|
|Supported Models||--||H3113 H4113 H3133 H4133 H3123||d850 d852 d855 f400 ls990 d851 va985|
|Kernel Version (2)||4.9.203||4.4.153||(Failed)|
Frequency bands (MHz) supported by the phones. For all, 2G means GSM, 3G
means HSPA, 4G means LTE, for which individual bands are listed. While
documentation is not very explicit, USA models of both the River and the
Pioneer are advertised for all USA carriers, i.e. Verizon, AT&T, T-Mobile,
Sprint, and virtual carriers. This means they do both GSM and CDMA. The
international models are GSM only. None of these phones support 5G. Update:
there's a sticker on the Pioneer's box saying
Only GSM! Note: phone does
not work on Verizon… or any CDMA carrier, only GSM carriers.
Please return phone without opening the box, thanks.
|850MHz||2G 3G 4G/5||2G 3G 4G/5||2G 3G|
|900MHz||2G 3G 4G/8||2G 3G 4G/8||2G|
|1700MHz||--||4G/4 (*)||3G 4G/4|
|1800MHz||2G 4G/3||2G 4G/3||2G|
|1900MHz||2G 3G 4G/2||2G 3G 4G/2||2G 3G 4G/2|
|2100MHz||3G 4G/1||3G 4G/1||3G|
See this Wikipedia article
about E-UTRA, which is the formal acronym for LTE. It has links to various
tables, specifically deployments by region. In particular, here is a table
mapping supported LTE bands to regions where they are likely to work for
Europe (ITU region 1) includes Africa;
America (ITU region 2) includes both North and South;
Asia (ITU region 3) includes Australia and India.
The River and Pioneer support all the bands listed here except 4 and 17;
the LG G3 supported bands are noted.
Comparing the candidates on features:
The main conclusion from the feature comparison is, on most aspects the phones are generally equivalent. But newness is important and the River leads here while the LG G3 is ancient. One disappointment is in intrusion protection: while the old Samsung Galaxy S5 has IP67, none of the current candidates is IP rated. I'm going to read reviews on the River, and come back to the Pioneer only if something really nasty turns up for the River. Which it did: no NFC.
The author likes the design, display, dual (?) rear cameras, turbo
charging, good battery life. He doesn't like the speaker. Low-light photos
general video quality aren't fantastic.
The Moto G7 is the best
budget phone we've tried, hands down.
Apparently the MSRP at inception was around $300 ($230 at Walmart).
It has Gorilla Glass front and back, which tends to attract fingerprints.
The display goes right up to the top of the chassis except for a notch for
the front camera. The display has rounded corners, and some apps are seen
to act weird in dealing with them. The fingerprint reader is on the back.
It has a headphone jack. The speaker is on the bottom, which is
often sounded tinny. Intrusion protection: IP54
(how come jimc didn't see this on the product page? Because it isn't there.)
The author devotes several paragraphs to a demo that the camera app is the main culprit in determining how good the photos are. He has a pair of photos of his sleeping cat, taken with the stock app and the one off the Google Pixel 2, stacked with a sliding window to show a fraction of each. The stock app tends to over brighten the picture, particularly white parts of the fur, while the Google app maintains dynamic range, and avoids over-sharpening the fine detail of the fur.
Playing looped video in airplane mode, the Moto G7 lasted almost 13 hours.
Flagship phones like the current iPhone model can outperform the Moto G7, but the Moto G7 comes very close to their level.
Pro: solid performance, long battery life, supports all US carriers,
attractive design. Cons: disappointing camera quality, mediocre call quality,
relatively pricey so he says. It's a Gorilla Glass shell with an
aluminum frame; he says it feels good in his hand.
The display is bright
enough to use in direct sunlight. On top is a
hybrid SIM / micro-SD
slot. (See jimc's note for the Pioneer.) On the bottom is the
speaker (82dB, loud), a USB-C port, and a 3.5mm headphone jack.
Testing cellular data on T-Mobile in Manhattan (heavily congested): he got
speeds of 22Mbps down and 17Mbps up, similar to other midrange phones tested.
He says NFC is missing. (Didn't jimc see this on the product page?
It's there, but with the word
He was pleasantly surprised by the Moto G7's performance. No problems with 12 apps open simultaneously. Playing a game for an hour used 14% battery. Streaming video over Wi-Fi at full brightness: the battery lasted just under 10 hour. He didn't like the camera.
This review was generally similar to the other two.
We've got a problem: the River does not have NFC, making Google Pay
impossible. The UK version may or may not have it, but we're not in the UK.
I'm going to have to use the contingency plan and read reviews of the
Sony Xperia XA2
Basics: Body: Aluminum frame, polycarbonate back; colors silver, black.
blue (cyan actually), pink. Extra info on hardware: Rear camera: steroidal
23Mpx, 1/2.3in (11mm I hope) sensor size, f/2.0, 25mm equivalent focal length.
Single/dual SIM (Jimc discovered: some models, but
not this one, have dual SIM sockets. Both are nano size. The second one is
placed sideways in the SD slot, so you can insert a SIM or a SD card but not
both. The River has a
hybrid SIM/SD slot but I haven't confirmed how
similar it might be.) LTE category 12/13 (600Mbps download, with tailwind),
USB-C, Wi-Fi abgn not ac, GPS, NFC, Bluetooth 5.x, FM radio. Fingerprint
reader on the back. Single speaker on the bottom. 3.5mm stereo headphone
jack. Physical camera activation key. In the box: phone, USB-C cable, generic
They like how it feels in the hand: yes plastic, but comfortable. The
black version may show fingerprints, though. Good backlit IPS display, equal
number of sub-pixels for each of RGB (unlike an earlier phone with weird pixel
layout). 500nit brightness (is this in the spec page?); they measured 530nit.
Contrast ratio at least 1300:1. Visibility in sunlight is
OLED is better; quantitative contrast ratio is 3.765 (best of IPS competitors)
vs. Samsung Galaxy A5 (2017) (OLED) at 3.804. The out-of-box color balance
was not to his liking, biased toward cyan, i.e. minus red, but this is
GSMArena's battery test: 21.3hr voice chat (3G), or 13.2hr web browsing, or 11.5hr video playback. If combined with an hour per day of each task and 21 hours of standby, it would scale to 92hr. This is pretty good, for them.
Speaker: voice chat on speakerphone (presumably turned to loudest)
is 69dB, music 73dB, ringer 78dB. Rated
For the rear camera, they praise the provided app, and don't complain about picture quality like the reviewers of the River. They do, however, say that the front camera lacks autofocus (which the XA1 had) and so is not as sharp.
Overall they think the Pioneer definitely deserves a recommendation.
It offers solid specs and performance for the price, but the
16:9 screen and chunky body are already out of step with the competition,
and the camera just can't keep up at all. In other words, it does a
cellphone's job well, but fails to follow styling trends. I want to see the
details of what he's complaining about on the camera. MSRP appears to be $500
at the time of review.
He praises the camera hardware, but pins the blame for underwhelming camera performance on the stock camera app. Note the different judgments about the software between this review and the one from GSMArena.
Battery life: he doesn't get too quantitative, but he reports 8.5hr on Geekbench's battery life test, which is better than a typical flagshop phone (from 2018) can do, he says. It comfortably runs longer than one day, but not two days.
Watch out, searches will return the Xperia XA2 Ultra (wrong phone), and
refurbished ones. Also the color radically affects the price. These reviews
are from the product page for the
Sony Xperia XA2 Factory Unlocked Phone - 5.2" Screen - 32GB - Silver
(U.S. Warranty). $315, sold by
Aimportar USA, fulfilled by Amazon.
Condition: New. ($500 if you want black, from a different vendor.)
Customer reviews distribution: 55% 5 star, 17% 4 star, 7% 3 star, 8% 2 star, 15% 1 star, 310 total reviews. In this I'm going to read recent reviews first, and I'll concentrate on negative ones to try to get advance warning of problems. They separate USA and international reviews (Canada is international), and I'm going to narrow down my work by looking at USA reviews (199 of them). I'll exclude 4* and 5* reviews since I already know the phone is wonderful:-) Here are summaries of the most useful negative reviews (and one positive):
This is the best phone bar none!Still running like the first day. A lot of bumps, scrapes and scratches on the metal bezel but the glass screen is pristine. No need for a case. Battery lasts for days running LineageOS. (jimc says: he is the only one that I read that mentioned LineageOS.)
If you're on a budget… it's a good phone.But its super thick. The screen scratches extremely easy. 23Mpx camera is too much; you can't focus it, it's blurry. (jimc says: likely she's got autofocus turned off and doesn't know how to turn it back on.)
I purchased the Pioneer.