> What's the hardest part about an open phone?

Very good question; what's holding us back really? If we want an open phone there should be more discussions on this. Some thoughts aided with chatgpt:

Easy: get display, sound, cellular, sensors, inputs working

Harder: (efficient) Power management, App ecosystem: distribution, SDK, compatibility, (tight) Privacy controls, (robust) Update delivery system, (vast) Hardware support, Backward compatibility, Accessibility, Localization, Customizability, Camera (apparently)

Beyond tech:

Proprietary hardware drivers: how do you get the hardware manufacturers' commitment to allocate their engineers to write drivers for the open phone system? Reverse engineering requires more effort and is not very sustainable.

Carrier requirements: Supporting and testing emergency services, lawful interceptions, certifications, possibly differing requirements for each carrier and regions.

Regulatory compliance: Constantly changing requirements by nations and geographical regions.

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Reading from the other comments, power management seems very hard to get right.

The non-tech reasons seem to be the most challenging; it introduces the most complexity and it's not exactly something that can be achieved by a passionate person in an evening