The idea of the modular cell-phone is not a new one. However I think its time for major effort and energy to be put into making this idea into a reality.
Cell phones are something that all of us consume. People are constantly looking for the next coolest/fastest/most exclusive cell-phone, and with 2-year cell phone contracts most people are used to tossing their old phones every couple of years. While the cell-phones of today would hardly be recognized by their ancestors components of phones aren't all that different. Case, screen, battery these are all things that can be made better and in a more modular way.
A new system would still allow people to get the best and fastest devices this could be done with software and hardware upgrades rather than completely replacing the unit.
In this way people in factories wouldn't loose jobs because modular parts still need to be made, you would need people to be able to do these hardware and software upgrades for consumers which could also add more jobs and companies could be incentivized to turn old parts into new parts or at least make components replaceable and removable.
You could recycle old parts two fold 1) Directly to manufactures to make new products 2) Into completely new products for lower income people/countries. So instead of shipping an old CPU that has no use to East Africa we can send parts that can actually be used to make something and don't require the hazardous work currently required to tare down electronics.
*note this focuses on cell-phones because they have become so common recently and are only going to get more so globally and I thought it would be easier to start with one thing rather that can then be translated to other products.
video and photos are not mine