After a few days of the Nexus 6, I found that I was having some extremely annoying orientation sensor issues that appeared to have their basis in software. For example, various apps would not reorient based on how I held the phone, even though the orientation sensor itself was working correctly. I also noticed that unlike the Samsung Galaxy S3, I could not conduct voice calls and transmit data simultaneously. This is a major issue and is completely unacceptable given the cost of the phone and the fact that I actually utilized that ability with my S3 on a regular basis.
I decided to try a custom ROM, specifically, Liquidsmooth. I used their “DarkUI” build and loaded GAPPS for CM12. After backing up my stock ROM with TeamWin Recovery, I flashed the LS and GAPPS zip files and rebooted. Everything worked pretty much flawlessly, and my orientation sensor issues are gone. I also have a few convenient features that were not present in the stock ROM, and I have not yet experienced any stability issues. Overall, I’m very satisfied with LS 4.0 as of now.
Regarding voice/data simultaneity, the situation is not as rosy. The reason that older phones like the S3 had the capability is that they had separate CDMA and LTE antennas. So while voice was transmitted over the CDMA antenna, data could transfer simultaneously on the LTE antenna. However, modern phones such as the Nexus 6 and iPhone 6 have only a single antenna, and consequently do not support true simultaneous voice and data. The workaround for this is using data for voice calls (voice over LTE, or VoLTE), something that Verizon supports currently on the iPhone 6. This feature is not supported for the Nexus 6 on Verizon as of now, most likely because the Nexus 6 itself is not supported yet. However, it is expected that Verizon will introduce support for this on the Nexus 6 very shortly as their support for the phone itself is imminent.
Overall, I am disappointed in the stock ROM (software) that came with the Nexus 6 because it introduced extremely annoying orientation sensor issues that a brand new, $650 device should not have. I am disappointed in the hardware for requiring carrier-level support for basic functionality that I took for granted on my older phone. The bottom line is that the end user should not be expected to jump through hoops and spend hours performing potentially risky procedures with brand new hardware (flashing the recovery partition and wiping out existing software) just to have things work acceptably. I am rather technically inclined and have done these types of procedures on several phones and other devices and the process still makes me cringe. It is well beyond what the average user is going to undertake.
Shame on Google and Motorola for releasing a product that is not ready for prime time right out of the box, and expecting us to pay almost $700 for it.