Why would model production cycles impact you in the Android world. My current app runs seamlessly on nearly 200 hundred different models (in India).
The application dev ecosystem and abstractions are very different in the Android world. Accessing the GPS is completely independent of underlying hardware and is already something we run happily on a daily basis.
On gpio - curious. What applications would you use it for ? Generally they are useful for attaching peripherals like GPS modules, wifi,etc....And I grant there might be some modules that you might need. But isn't the phone solving the 99 percentile use case without need for gpio?
GPS or Wifi could easily be attached via USB, you don't need GPIO for that. The huge benefit of GPIO ports are all those things that DON'T have standard ports like USB: sensors (temp/humidity/air, radar, …) or controlling lights (e.g. LED strips) or other basic electronics that you wire to your SBC.
Really the GPIO pins are what makes SBCs so great for me... a smartphone is just a closed-off portable computer with very limited built-in sensors.
No more than a phone solves the 99 percentile use case better than a small PC does.
I have a custom-built fluid handler built from a Rpi and a $20 3.5" touchscreen, a $6 Arduino relay board and some additional hardware. I need the GPIO to run pumps and valves and additional I/O. Could it be done on a phone? Yes, with additional hardware and more effort. The lower cost of the phone would be eaten up in the first hour it took me longer than on the Pi.
I've recommended to many people contemplating complex Arduino projects that they move to the Pi instead. Often, by the time you purchase multiple Arduino "shields" to do a task, you're well past the price of a Raspberry Pi that has all the needed I/O: networking, audio output, storage and more built in.
Hell, I'm involved in a high-speed signal processing project where I use an Arduino M0 for the speed but I still needed to do some of the behavior in analog circuits because the Cortex M0 still wasn't fast enough to process everything digitally. I would have preferred to use a Pi but I don't trust the reliability (industrial application), and I need guaranteed real-time behavior.
I wholeheartedly agree with you that many hobbyist RPi projects could be done just as well on a phone: I noticed that quite some time ago. But hardware is less and less the limiting factor these days. Learning curves can be expensive. I tend to build things in small volumes, so any price savings from using a cheap phone or tablet is often meaningless in comparison to how long it will take me to get up to speed on a new platform.
The application dev ecosystem and abstractions are very different in the Android world. Accessing the GPS is completely independent of underlying hardware and is already something we run happily on a daily basis.
On gpio - curious. What applications would you use it for ? Generally they are useful for attaching peripherals like GPS modules, wifi,etc....And I grant there might be some modules that you might need. But isn't the phone solving the 99 percentile use case without need for gpio?