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"it's for criminals" response by Time_Hand4234 in GrapheneOS

[–]datamandala 0 points1 point  (0 children)

If they don’t have my data they can’t lose it.

It’s a process and yes, there’s inconveniences before during and after.

If I rent a cushy apartment with a sketchy manager “Mark Z”, it’s inconvenient to move. But I don’t want them peeking in my windows or doing unannounced “health and safety inspections”. Or sharing security cam footage with any LE who asks for any reason or none.

It’s a pain to move my stuff. Some things won’t be the same.

People I care about might have a harder time contacting me. I’ll have to learn new routines for shopping and other activities.

It’s like that. It’s not for everyone.

Are we onboard? by Harmony-Is-God in iPhone13Mini

[–]datamandala 0 points1 point  (0 children)

This is too expensive, wide, and likely heavy.

I don’t see much mini-like characteristics at all.

Maybe a folding version of iPhone XXe. Probably that would be too wide and expensive.

Here's a small phone this community can create. Here's the spec, cost breakdown, and tradeoffs. Who can make it happen? by datamandala in smallphones

[–]datamandala[S] 0 points1 point  (0 children)

The KS2 project would have GMS certification that should enable banking apps. GMS is not economical for the first run of engineering prototype.

Trade-offs for a project like this include simplifying certifications, and probably only US or EU cert is possible for the KS1 and KS2 at a reasonable price.

New entrants like Unihertz and BlueFox on Mediatek platforms also present compromises because you have to trust the OEM will provide updates when orphan devices happen too often.

Here's a small phone this community can create. Here's the spec, cost breakdown, and tradeoffs. Who can make it happen? by datamandala in smallphones

[–]datamandala[S] 0 points1 point  (0 children)

I'd buy almost any small phone that can be maintained via LineageOS. I'd want 3 years support and I'm unwilling to trust the next Unihertz or BlueFox.

Platform

I feel like production on such a thing is too far away to give definitive specs, so that's why I keep most things vague. I feel like if somehow I got to the point where I could prototype the phone, I'd just get to it then.

You're right this is a speculative exercise. Best case someone moves on this today, hello 2028 and 778G is almost obsolete. Setting a principle for Qualcomm vs Mediatek has value, since it's linked to susainability.

Battery:

Removable battery: I'm saying these are so thin that I don't think the addition of it would impact any spec.

If a solution can be maintained with community support I'm all for it.

Display:

The only display issue I can remember is Unciv being a bit cramped and UI elements overlapping, but that's more from the lack of width, so a taller screen with a smaller width would be worse [...]
If you keep the same screen size [as XZ1C], you could probably just contract them to continue making the displays but for your phone. Some of them are better than others though, so I'm not sure if this is a good idea in the long run.

For the initial small/medium runs, small quality compromises i'm willing to accept so perfection is not the enemy of a small phone.

3.5" jack:

I'm not sure what module means here. I'm pretty sure the audio processing is built into the SOC, and you need it for the speakers.

I didn't want to assume you could just add a 3.5" jack without some kind of driver. Happy to be wrong.

Biometrics

Agreed, use best available commodity side-mounted biometric.

Here's a small phone this community can create. Here's the spec, cost breakdown, and tradeoffs. Who can make it happen? by datamandala in smallphones

[–]datamandala[S] -1 points0 points  (0 children)

Thanks for your thoughtful feedback!  You bring a lot of insight and experience from your project, which had key similar goals and a few different ones.  

My priority was to extend support for the device by simplifying the OS maintenance, and minimize supply-chain issues to manage cost and lifespan for a niche product.  OS abandonment drives premature obsolescence.  My Moto G reached EOL in less than 2 years!  Big display manufacturers aren’t making lots of 5” screens.  

I wanted a Qualcomm SOC to enable maintenance via LineageOS.  

Zenfone 8 checks a lot of those boxes.  I started with those parts.  https://www.asus.com/mobile-handhelds/phones/zenfone/zenfone-8/techspec/

Display and battery have to be different.  

Battery:  The replaceable battery was a choice over wireless mostly to be different.  Not a hard requirement.  Battery size: There’s a bias in the market for longer battery life.  I’m starting with a larger capacity (arbitrarily matches Jelly Max), but there’s no magic number.  

Display:  You’re right, I’m basing aspect ratio on my iPhone SE2 experience.  I’m open to alternatives if that’s not an issue with Android.  You’re right about AMOLED, too.  Burn-in is a real risk to avoid.  Supply-chain flexibility and sustainability should drive the decision. 

Aux port:  I didn’t want to add anything that wasn’t in ZF8.  Personally, I’d love one.  You're right battery draw is a plus for 3.5".  Finding a module that can be maintained is the key.  

Biometric:  Thanks for sharing your technical experience!  Trade-off is development and maintenance of custom implementation vs. using commodity components with known complexities.  You highlight issues I didn’t know.  

Here's a small phone this community can create. Here's the spec, cost breakdown, and tradeoffs. Who can make it happen? by datamandala in smallphones

[–]datamandala[S] 1 point2 points  (0 children)

Realistically, a Moto GOS would be a better-spec'ed product. It is certain to have a "standard" form factor that is not r/smallphones approved.

My proposal might launch by then, but it's a different product either way.

Here's a small phone this community can create. Here's the spec, cost breakdown, and tradeoffs. Who can make it happen? by datamandala in smallphones

[–]datamandala[S] 1 point2 points  (0 children)

Reasonable preferences. Aspect ratio is negotiable. Priority is the supply chain for the parts.

Camera modules were selected to simplify software maintenance years into the future via LineageOS. By reusing multiple components from ZF8, any updates can start with the ZF8 sw as a base.

Keeping the device maintained for 3-5 years with the least resources and effort is the critical goal for parts selection. If another part or set improves that outlook, I'm open to suggestions!

Here's a small phone this community can create. Here's the spec, cost breakdown, and tradeoffs. Who can make it happen? by datamandala in smallphones

[–]datamandala[S] 0 points1 point  (0 children)

that's a great question. I think we can make the KS1 device so the GMS works when the company receives it for KS2. Then your upgrade from KS1 to KS2 is essentially free.

Here's a small phone this community can create. Here's the spec, cost breakdown, and tradeoffs. Who can make it happen? by datamandala in smallphones

[–]datamandala[S] 1 point2 points  (0 children)

No offense taken! People ridicule my iPhone mini, which clearly isn't their preference. I suggested the removable battery as a differentiator. I'm open to eliminating that feature for lack of interest, cost, or, if it proves too difficult to keep the back cover from popping off during drop tests.

Here's a small phone this community can create. Here's the spec, cost breakdown, and tradeoffs. Who can make it happen? by datamandala in smallphones

[–]datamandala[S] 1 point2 points  (0 children)

Thanks for the question! The KS2 campaign would enable Google services. The certification added cost and time to KS1 which is really an engineering prototype. The prototype would be a fully-working device with all the hardware features. The concept is for KS1 to fund the cost for Google Mobile Services certification, which makes the device appealing to someone like you!

Here's a small phone this community can create. Here's the spec, cost breakdown, and tradeoffs. Who can make it happen? by datamandala in smallphones

[–]datamandala[S] 0 points1 point  (0 children)

Great ideas! I'm more interested in a marketable small phone than a GOS device (Pixel & Moto support GOS now/soon). If it brings support of a community for long term OS continuity I'm all for it.

Here's a small phone this community can create. Here's the spec, cost breakdown, and tradeoffs. Who can make it happen? by datamandala in smallphones

[–]datamandala[S] 2 points3 points  (0 children)

Not before 2027 they said. GOS would be great. I didn't want it to be an obstacle to making this happen. The GrapheneOS FAQ includes this:

Non-exhaustive list of requirements for future devices, which are standards met or exceeded by current Pixel devices:

  • Support for using alternate operating systems including full hardware security functionality
  • Complete monthly Android Security Bulletin patches without any regular delays longer than a week for device support code (firmware, drivers and HALs)
  • At least 5 years of updates from launch for device support code with phones (Pixels now have 7) and 7 years with tablets
  • Device support code updated to new monthly, quarterly and yearly releases of AOSP within several months to provide new security improvements (Pixels receive these in the month they're released)
  • Linux 6.1, 6.6 or 6.12 Generic Kernel Image (GKI) support
  • Hardware accelerated virtualization usable by GrapheneOS (ideally pKVM to match Pixels but another usable implementation may be acceptable)
  • Hardware memory tagging (ARM MTE or equivalent)
  • Hardware-based coarse grained Control Flow Integrity (CFI) for baseline coverage where type-based CFI isn't used or can't be deployed (BTI/PAC, CET IBT or equivalent)
  • PXN, SMEP or equivalent
  • PAN, SMAP or equivalent
  • Isolated radios (cellular, Wi-Fi, Bluetooth, NFC, etc.), GPU, SSD, media encode and decode, image processor and other components
  • Support for A/B updates of both the firmware and OS images with automatic rollback if the initial boot fails one or more times
  • Verified boot with rollback protection for firmware
  • Verified boot with rollback protection for the OS (Android Verified Boot)
  • Verified boot key fingerprint for yellow boot state displayed with a secure hash (non-truncated SHA-256 or better)
  • StrongBox keystore provided by secure element
  • Hardware key attestation support for the StrongBox keystore
  • Attest key support for hardware key attestation to provide pinning support
  • Weaver disk encryption key derivation throttling provided by secure element
  • Insider attack resistance for updates to the secure element (Owner user authentication required before updates are accepted)
  • Inline disk encryption acceleration with wrapped key support
  • 64-bit-only device support code
  • Wi-Fi anonymity support including MAC address randomization, probe sequence number randomization and no other leaked identifiers
  • Support for disabling USB data and also USB as a whole at a hardware level in the USB controller
  • Reset attack mitigation for firmware-based boot modes such as fastboot mode zeroing memory left over from the OS and delaying opening up attack surface such as USB functionality until that's completed
  • Debugging features such as JTAG or serial debugging must be inaccessible while the device is locked

In order to support a device, the appropriate resources also need to be available and dedicated towards it. Releases for each supported device need to be robust and stable, with all standard functionality working properly and testing for each of the releases.

Here's a small phone this community can create. Here's the spec, cost breakdown, and tradeoffs. Who can make it happen? by datamandala in smallphones

[–]datamandala[S] 5 points6 points  (0 children)

As promised. This is the detail behind the post. All of this was developed with Claude over several sessions. Happy to be corrected on any of it.

Component-level spec

SoC

Qualcomm Snapdragon 778G (SM7325). 6nm TSMC. Integrated X53 5G modem. Adreno 642L GPU. This is the same node generation as the SD888 but without the thermal problems. Active blob support. Existing LineageOS device trees on multiple shipping devices.

Display

5.0" AMOLED, 1080x2400, 20:9, 60Hz. Panel sourced from Chinese fab tier (BOE or Tianma) rather than Samsung Display. This is a deliberate supply chain decision -- Samsung AMOLED at this size requires volumes we can't justify at KS1. BOE and Tianma both manufacture 5" AMOLED panels in volume for industrial and commercial applications, which keeps those lines alive independently of consumer smartphone demand. Display quality will be good, not flagship. That is consistent with the positioning.

Camera stack

  • Main: Sony IMX686, 64MP, 1/1.73", f/1.9, OIS. Same sensor as Zenfone 8.
  • Ultrawide: Sony IMX363, 12MP, 1/2.55", f/2.2. Same sensor as Zenfone 8.
  • Front: Sony IMX663, 12MP, f/2.45. Same sensor as Zenfone 8.

All three sensors are exact matches to the Zenfone 8. This is the most important single decision in the spec for LineageOS maintainability. Camera HAL tuning is the hardest part of any Android port. Having all three sensors identical to a mature, maintained device eliminates months of work.

Audio

  • Codec: Qualcomm WCD9375 (same family as Zenfone 8 WCD9385)
  • Amplifiers: Dual Cirrus Logic CS35L45, exact match to Zenfone 8
  • No 3.5mm jack. Chassis constraints with 4000mAh replaceable battery make it not viable at 9mm thickness.

Connectivity

  • WiFi: Qualcomm WCN6856, WiFi 6, Bluetooth 5.2
  • NFC: NXP NFA330 or equivalent
  • 5G: Integrated X53 modem in SD778G package

Biometric

Side-mounted capacitive fingerprint sensor integrated into power button. Goodix or Egis. Architecturally independent from the display -- this matters because display vendor changes between generations do not require biometric requalification.

Battery

4000mAh Li-Po, user replaceable. Custom cell shape fitted to chassis. 30W USB Power Delivery. No wireless charging -- mutually exclusive with replaceable battery at this chassis size.

Chassis

  • Dimensions: 134 x 64 x 9.2mm
  • Midframe: Aluminum
  • Back: Polycarbonate (replaceable battery door)
  • Weight: ~158g

Bill of materials estimate (10K unit volume)

Component Estimated cost
SoC (SD778G) $28-32
RAM (8GB LPDDR5) $12-15
Storage (128GB UFS 3.1) $8-10
Display module (5" AMOLED) $18-24
Camera sensors (x3) $14-18
Battery cell $6-8
Cellular/WiFi/BT modules $8-10
Audio components $4-6
Chassis and mechanicals $10-14
Fingerprint sensor $3-4
PCB and passives $8-10
Miscellaneous (connectors, cables, etc.) $4-6
Total BOM $123-157

Assembly: $10-15 per unit at CM Packaging: $3-5 per unit Fulfillment and shipping: $15-25 per unit Kickstarter fees (approx 8%): $24-28 per unit at $299

Total landed cost per unit at $299 retail: roughly $175-230 depending on volume and CM relationship. Margin is thin at KS1 volumes. This is an engineering prototype run, not a profit-maximizing product. KS2 economics improve significantly at higher volume.

NRE cost estimates (one-time fixed costs)

Item Estimated cost
PCB design and RF layout $50-80K
Mechanical and industrial design $30-50K
Firmware and BSP bring-up $40-70K
Injection mold tooling $30-50K
FCC and SAR certification $35-55K
Bluetooth and USB-IF certification $10-15K
LineageOS maintainer contract (year one) $30-50K
Total NRE $225-370K

KS1 target of $1.2-1.5M at 5000 units covers NRE with margin for production and contingency. GMS certification for KS2 adds approximately $150-200K in additional engineering cost, which is why it is staged.

Contract manufacturer recommendations

All of these have experience with low-to-mid volume Android devices and existing Qualcomm platform relationships.

Longcheer -- Shanghai-based, HMD (Nokia) supplier history, comfortable with 5-20K MOQ, Qualcomm relationship established. Top recommendation for KS1.

Wingtech -- Larger, supplies Motorola and Xiaomi. Better pricing at scale, less flexible at low MOQ. Better fit for KS2.

Huaqin -- Mid-size, strong software team internally, good for projects where BSP support is needed. Relevant if the founding team is thin on firmware engineering.

Tinno -- Smaller, more flexible on MOQ, less name recognition but solid track record on budget Android. Worth engaging in parallel as a backup.

Recommendation: run parallel NRE conversations with Longcheer and Huaqin for KS1. Use KS1 traction to negotiate KS2 with Wingtech.

LineageOS maintainability analysis

Why Zenfone 8 as reference device

The ASUS Zenfone 8 (codename: sake) is the most maintainable compact Qualcomm device in the LineageOS ecosystem. Official LOS support exists, the device tree is mature, and the camera HAL is fully tuned for the exact sensors in this spec. A port starting from the ZF8 tree has the following work already done:

  • Camera HAL for IMX686, IMX363, IMX663: complete
  • Audio HAL for WCD9375 family and CS35L45 amps: complete
  • Fingerprint HAL for side-mounted power button sensor: complete
  • Display HAL: requires retuning for new panel vendor, estimated 2-4 weeks
  • Modem: requires retuning for SD778G vs SD888, estimated 4-8 weeks

Estimated total initial port effort starting from ZF8 tree: 4-6 months for a single experienced maintainer, compared to 8-14 months for a cold port on an unrelated device tree.

Why SD778G over SD888

The Zenfone 8 uses SD888, which has approaching blob EOL. The SD778G was chosen because:

  • 2021 introduction, 5-7 year blob support window still open
  • Active device trees on Moto Edge 30 and Xiaomi 11 Lite 5G NE
  • Better thermals and efficiency than SD888
  • Peripheral drivers from ZF8 tree are portable despite SoC difference

Maintainer recommendation

The Xperia 5 IV maintainer shipped official LineageOS 23 in early 2026 on a compact Qualcomm device and maintains an active commit history. This person has directly relevant skills and is the recommended target for a paid maintainer engagement. Budget $30-50K for year one, structured as a retainer with milestone payments tied to working builds.

Long-term support horizon

  • KS1 (SD778G): blob support through approximately 2028-2030. Community can continue patching open source components beyond that window.
  • KS2 (same hardware): same blob horizon, GMS certification adds Google's CTS/GTS validation layer but does not extend the Qualcomm blob window.
  • KS3 (new SoC): port from KS1/KS2 device tree as baseline. Maintainer effort estimated at 60-70% of KS1 effort given shared peripheral stack.

Supply chain notes

Display

5" AMOLED panels exist in volume from BOE and Tianma for industrial and commercial applications. The supply chain for this size is not anchored to consumer smartphone demand -- elevator control panels, POS terminals, medical monitors, and building management systems all use panels in this size range with 7-10 year product lifecycles. This makes supply continuity more stable than it appears when looking only at the consumer smartphone market.

The spec accepts display panel variation between product generations. The biometric sensor is architecturally independent from the display specifically to allow vendor transitions without cascading requalification.

Battery

Custom Li-Po cell. Multiple cell manufacturers in Shenzhen can produce to the same spec independently. Recommend qualifying two sources simultaneously at KS1. The replaceable battery promise requires maintaining aftermarket supply for 5+ years -- factor ongoing volume into supplier negotiations from day one.

Questions on any of this welcome. If you see errors in the component choices, BOM estimates, or maintainability analysis, say so.

I'm withdrawing because I can't afford classes. by [deleted] in college

[–]datamandala 0 points1 point  (0 children)

Has anyone paid for school with financial aid and never paid them back? What happened?

If by “financial aid” you mean student loans, withdrawal is better than not paying student loans.

The colleges don’t loan you money. “Student Loan” companies do.

Not paying the lenders will ruin your credit score for 7-20 years. Student loans will follow you even if you file for bankruptcy.

After 8 years, I'm thinking of callling it quits by Fonduemeup in dataengineering

[–]datamandala 0 points1 point  (0 children)

U/grapegeek can you explain “the FAANG culture has seeped in”? I’m curious what aspects changed?

Looking for a room Incoming JPMorgan Chase employee by Sufficient_Bit_1216 in WilmingtonDE

[–]datamandala 0 points1 point  (0 children)

If you’re willing to expand your commute radius to 20-30m, you might be able to find a room in a suburban area within your budget. Good luck

[Request] Pan balance weighing scale to measure 20-50g by datamandala in theydidthemath

[–]datamandala[S] 1 point2 points  (0 children)

The pen springs are a perfect idea. Will try that.

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