I'm using a Fairphone 4 smart phone, running the MicroG-enabled LineageOS instead of the default software (ROM).
Unfortunately, the phone has several shortcomings:
Ghost inputs
Sometimes the touch screen triggers scrolls, swipes and zoom gestures without anyone touching it.
Thousands of FP4 users had this problem, and it was fixed in the official Fairphone software version Fairphone OS version B.086:
Ghost touches: an issue that causes the user interface to move or jump without touching the screen.
Unfortunately the fix is not available on LineageOS 20 (2024-01-05), which means I still experience the problem.
I once disassembled the phone, "cleaned" the display contacts by blowing onto it and re-assembled it. Afterwards the ghost touches appeared less often.
Enabling "touch visualization" in the Android developer settings gave me this screenshot of ghost inputs:
Touch screen does not work without touching the frame
Sometimes the touch screen does not work (does not recognize touches) when the phone is lying flat on a table or my lap. When touching the frame it becomes responsive again.
Other people also reported this problem:
All we know is that there is some empirical evidence that the FP4’s touchscreen now requires the phone to be connected to some larger conductive body to reliably work – Either the user also touching the phone’s chassis, or the phone being connected to something else by its USB cable (like while charging it).
KurtF, 2023-08-26, Software update: FP4.SP2J.B.086.20230807
The Fairphone 3 already had this problem:
Seit ich das FP3+ habe funktioniert das Touch Display nicht,
wenn ich es auf den Tisch lege.
Wenn ich es in die Hand nehme, ist alles in Ordnung.
Lotta_Hund, 2021-05-06,
FP3+ Touch Display funktioniert nicht, wenn es liegt
Bad speaker sound
I can't listen to podcasts via the Fairphone 4's built-in speakers because the sound is awful. My ring tone and message notification sounds also sound very tinny.
This hardware problem is known and acknowledged by the Fairphone developers:
Time to call it. It’s a hardware problem that we could mitigate in software by artificially reducing the volume of the top speaker. We believe that a blanket volume reduction will be perceived negatively by the majority of users, so we opted to leave it as it is.
The workaround described above (Accessibility Settings > Mono > balance all the way to the left) works in most cases. [...]
We’ve learned a lot from this investigation and we’ll use these lessons when designing future products.
Yasen_Tomov, 2023-06-08, Check for and replace blown speaker
For me the workaround is to use the Android accessibility settings to downmix all sounds to mono and move them to the right speaker (bottom of the phone), completely bypassing the right speaker (top of the phone).
Bad compass
I love to use SkyMap (F-Droid) to see which stars are visible in the sky at night.
Unfortuantely the compass on the Fairphone 4 is so bad that the map just jumps around and shows a totally different direction when rotating the phone for a couple of degrees.
As usual, other people have the same problem:
In almost all cases, the orientation error ranges from 45 to 180 degrees.
ChristianH, 2023-01-25, FP4: The compass is unreliable
Moving the phone in a "8"-pattern several times while Skymap or the compass app is open did improve accuracy quite a bit, but I have to recalibrate every time I use Skymap.
