@GrapheneOS

GrapheneOS

It's useful to keep it plugged in because it has bypass charging to use power directly from the charger without going through the battery. It shows the shield icon while doing this. The battery will last even longer if you leave the device plugged in since it's avoiding using it.

As also asked in the dedicated "New Battery Bypass feature in GOS?" thread:

Does the battery bypass require the use of a USB-C Power Delivery charger with PPS (Programmable Power Supply) feature support?

Or does it work with any USB power source?

Samsung devices apparently require the use of a USB-C Power Delivery charger with PPS feature for the battery bypass (called "Pause USB Power Delivery" on Samsung devices) to work.

In the following random example video, the power meter seems to indicate that the phone is essentially constantly drawing around 8 Volts from the PPS power supply when using the battery bypass mode:

https://www.youtube.com/watch?v=YvAWT-zIWhQ

Maybe this is because batteries typically output around 3.7 to 4.2 Volts and therefore maybe a phone still requires this voltage range when bypassing the battery. Maybe in this case the phone has a built-in voltage step down converter to half the around 8 Volts to around 4 Volts to then constantly operate at around 4 Volts in the battery bypass mode.

That maybe could explain why a PPS compatible USB-C power supply is required for the battery bypass. Because only PPS compatible power supplies are able to output variable and dynamic inbetween voltage values, whereas non-PPS power supplies are limited to fixed voltage values such as 5 Volts and 9 Volts for example.

Maybe someone can clarify if Pixel devices also require a PPS compatible power supply for the battery bypass feature to work.

      DeletedUser130 generally, you manipulate amperage, not voltage. The voltage always stays constant. The amperage goes up or down depending on power draw.

          de0u Baseline Verizon functionality works fine but we recommend using anything else. Verizon is the only carrier requiring a bunch of carrier-specific bloatware apps to use various basic functionality.

              • Dde0u

                • Post #71

                DeletedUser119 I think the most useful experiment would be flashing GrapheneOS A15 on a new device and trying a new Verizon SIM, to be sure that provisioning works. I am not personally in a position to run that experiment at present.

                    • Dde0u

                      • Post #72

                      GrapheneOS Baseline Verizon functionality works fine but we recommend using anything else. Verizon is the only carrier requiring a bunch of carrier-specific bloatware apps to use various basic functionality.

                      They're also a "leader" in terms of non-flashable devices. But they're a major carrier in the U.S., and in some areas their coverage is the best.

                        hey, first of all thanks for the new fingerprint + pin unlock method. i really like it and it works great. one thing i have noticed though is that in apps like infinity or signal, my unlock method now also has switched to fingerprint unlock but it does not ask for the pin as a second factor. is that a bug or intended behavior?

                          de0u It should still work fine. We're only getting reports of issues with several of their MVNOs since Android 15 QPR1. We know it's because the Verizon bloatware isn't included which we aren't willing to do. It's a significant privacy and security issue.

                            nimmi It's fully intended that it doesn't add the 2nd factor PIN anywhere other than the lockscreen. It wasn't within the scope of the feature we decided to implement.

                              • Rryrona

                                • Post #76
                                • Edited

                                GrapheneOS It starts with scrypt in the OS but it finishes with a device-dependent key derivation algorithm in the TEE.

                                Yeah, but the information I have is that scrypt is the only two of them that is memory hard, and scrypt is kind of "nerfed" compared to how it should be used, so it would still be equivalent to PBKDF2 in that table.

                                I wasn't trying to make a case for improving the key derivation security in GrapheneOS this time, even if I did that a year ago. I was just trying to tell how many words are needed for which security level, as things are today.

                                  DeletedUser130 Maybe someone can clarify if Pixel devices also require a PPS compatible power supply for the battery bypass feature to work.

                                  Interested to find the answer, too.

                                  DeletedUser87 generally, you manipulate amperage, not voltage. The voltage always stays constant.

                                  That was valid for old-day chargers, not possible anymore with powerful ones supporting rapid/quick charge and dynamic power management to optimize the speed and safety.

                                  The amperage is limited up to 5A, so the cables and connectors survive. To deliver more power they have to manipulate the voltage.
                                  PD uses negotiable voltages 5,9,12,15,20V, while PPS can use a range from 3.3 to 21V. And yes, the charger can change the voltage during the charging process.
                                  Pixel 6/6Pro, 7/7Pro, 8/8Pro utilize PPS. Source.

                                        Oggyo qp5235 Maybe someone can clarify if Pixel devices also require a PPS compatible power supply for the battery bypass feature to work.

                                        Interested to find the answer, too.

                                        Same here. Also, I wonder, does having USB-C port set to charging only make any impact on charging with a PPS compatible power supply and thus (potentially) the bypass feature? Particularly, does it make charging "dumber" (e.g. falling back to standard PD instead of PPS) due to phone not being able to communicate with the charger? Perhaps negotiating charging mode doesn't need USB data exchange capabilities?

                                        Thanks a lot for the new features! I really appreciate it!

                                          Running this build via Stable channel on my Pixel 8 Pro. I'm running into a wierd bug when connecting via Bluetooth to my older Ford vehicle's MyFordTouch infotainment system. I can connect for calls and messages but I can no longer connect for media audio. Bluetooth media is still working for my headphones. It's only in my car where I can't get media audio anymore. Was working a few days ago.

                                          I've already tried forgetting (on both the phone and the car) and re-pairing to no avail. I also unfortunately cannot rule out the possibility of my infotainment system getting an OTA update causing a bug. However, I think that's fairly unlikely.

                                          I have yet to try anything along the lines of changing AVRCP or MAP versions in developer settings.

                                          Any ideas for further troubleshooting?