>How could we benefit from having Linux on old iDevices?

On old devices that do not get updates your internet will stop working because of old browser, missing SSL certificates or old libraries. With Linux you might get an updated browser and you could use the device to browse things and you can do whatever your mind can imagine like maybe write a simple bash/python script to automate something.

Technically yes, but when?

I just retired an iPhone5 that we were using as a "house controller", streaming Pandora, home automation app, etc. I retired it not because the software stopped working but because the battery won't last more than 30 minutes off the charger, and I had an iPhone8 sitting around doing nothing.

IMO an iPhone with linux is going to be less of "do whatever your mind can imagine" and more of "spend countless time trying to hack random stuff into this unsupported platform".

Overall, I think it is cool achievement, but (to me), it feels more along the lines of solution looking for a problem than an actual truly useful thing.

So this is not for you or people like you, could be a solution for poor people, all my computing devices were old second hand stuff ntill I had a good job to afford some new average PC. Android devices also suffer from this issue, some where some stuff gets outdated and many webpages or apps will not longer work for you because of security reasons forcing you to get a new device.

>IMO an iPhone with linux is going to be less of "do whatever your mind can imagine" and more of "spend countless time trying to hack random stuff into this unsupported platform".

That does not generalize, sure you can't imagine what you could use a device like that and the freedom but others can. On my Linux desktop I have a one line script that will speak the time to me every 15 minutes (I need it) or I have a script that when I press a button it will OCR the screen and read it to me. Sure 99% of people will buy an app that might do a similar thing or just give up BUT people like me just think "would be cool if this would work and we do it".

And don't try to accuse me that it took me 12 hours to make a button to OCR my screen or other bullshit accusations, you can spend 5 minutes googling what package does a screen grab, what package does OCR from image, then you combine the 2 packages and done , 5 minutes and I had hours saved and sometimes made impossible stuff possible .

Not everything has to be useful. Many years of “useless” hacking has given me a lot of experience and a great career.

Plenty of end of life uses work just fine living off of a charger. For instance, setting up an old iPad or iPhone as a home hub (https://support.apple.com/en-us/HT207057) requires the device stay plugged in already. I can imagine plenty of cases where an old phone could be a suitable substitute or even an upgrade over a Raspberry Pi (Pi-hole, Home Assistant, Spotify hookup for an old home stereo, etc.).

If the battery is absolutely crucial for your use case, quality replacements can still be had. The iPhone 5 battery, for instance, can be replaced for $30, with all needed tools included: https://www.ifixit.com/Store/iPhone/iPhone-5-Battery/IF118-0...

Anything that keeps perfectly usable devices like these out of landfills is a win in my book.

A somewhat newish iPhone would be more powerful than the raspberry pi. And I have got good use out of the pi for hosting game servers for small numbers of users. You can also get old apple devices way cheaper than new equivalent single board computers.

And the iPhone has a built-in touch screen, wifi, bluetooth, two cameras, internal storage, a GPU, a bunch of sensors, a giant battery, physical buttons, speakers, microphone, a giant market for third-party peripherals, cases, chargers, mounts, etc...AND it's way easier to get your hands on an iPhone (especially an old one) than a Raspberry Pi today.

Sure, getting everything to work in a Linux port wouldn't be easy, but it does clearly show the value of such a thing.

I wonder about the implications of running them in an "always-on" configuration. Would it be possible to remove the battery and run them entirely on AC power? If you could do that, you might be able to have some pretty nice low-power home servers.

If you just want a server, you can use an android phone already. Either pick one that works with postmarketOS, or termux could work fine (I don't know the overhead of that though). No point in using an iPhone here.

You could just buy a $2,000 2u rack mounted machine too... or you know, flash an old iphone you have sitting around with Linux.

When the project will be ready using an iPhone would make a lot of sense. My point was that it's currently not, but old Android phones do fine too.

What should I do with my old iPhones then?

Assuming they're ok with being kept on 24/7, they could become IoT terminals. A 10 years old phone should still have enough horsepower if it contained the bare minimum to load just one program that speaks to the home network, or a mpd remote to play music in the given room, communicate through VoIP with other terminals, etc. They could be used also in a lab to show data coming from instrumentation, as secondary display for servers etc. Plenty of uses; the only limitation being represented by the roadblocks (binary blobs, lack of documentation, closed drivers etc.) corporations put in place to prevent any further use of those devices that goes beyond what they have planned.

> Would it be possible to remove the battery and run them entirely on AC power?

Unfortunately, it seems this is not possible. https://www.ifixit.com/Answers/View/316746/Will+this+phone+t...

I removed the battery cell from a Samsung battery and powered the battery IC with the nominal DC cell voltage from a power supply. The phone then indefinitely showed a full battery. This might also work with an iphone

I've thought of using older Pixel phones for something like this. One annoying downside is that the Pixel devices do not tend to have an easy way to enable hdmi out.

And as a bonus they come with GPS, compasses, accelerometers, and of course network connectivity, out of the box (if you can figure out how to access them, anyway).

Its good for devices that stopped receiving iOS security updates, or for doing weird things that you can't do with iOS, like using your iPhone as a USB keyboard for your desktop using Linux's USB gadget support.

> Would I be able to repurpose a device to do something useful I can’t do with iOS?

How about doing anything at all? I have an iPad 2 and an iPad mini sitting around that aren't useful at all. Just sitting there, collecting dust because I don't have the heart to chuck them.

This, and the overall build-quality of the devices makes it hard to just discard them. Even their batteries are still mostly good. I’d love to repurpose them, have several here aswell lying around.

I don't know, but iDevices are more ubiquitous than other phones. It's much easier to source 100 of iPhone 6 than to collect same number of, Nexus ... whatever.

We still have an original iPad at an older relative. It's perfect for Solitaire.

It also used to be usable to load a weather page but turns out Safari doesn't know the certificate authority since it's such an old version. I guess such an old Safari is a walking security risk too.

It would be nice to be able to put Linux on it.

Realistically? Hackers who use new phones/pads are gonna repurpose them for some idle fiddling with the TV at home. That’s the extent of this “reducing e-waste” goal.

Yeah, it would actually be a useful computer.

I'm using one of my old android phone to run node-red and display a dashboard on it.

I want to use my old iphone 4 like this

I don't know if it's worth it but maybe contribute to cloud compute like DreamLab