Not with smartphones. There's a reason an old raspeberry pi, a device with a fraction of a smartphone power - and without a screen to booth, it an infinitely m

Not with smartphones. There's a reason an old raspeberry pi, a device with a fraction of a smartphone power - and without a screen to booth, it an infinitely more valuable device. You can buy used smartphones on ebay for nothing. They are being thrown out. Why don't we see those used for something other than alarm clocks and fancy picture frames? The truth is that you can use a raspberry to do anything you want but converting an old, even unlocked, smartphone to something which is not a screen for a browser is incredibly, INCREDIBLY hard. Getting to run plain linux on these devices and take advantage of the screen or other peripherals is generally a waste of effort due to binary drivers. What you get in most of the cases will be serial access and a flash drive for storage. Keeping android on it only forces you to develop for an OS that doesn't want you to be in control OR get access to the system. As soon as your typical smartphone gets out of support, it becomes e-waste.