Mega-kudos to the author for chipping away at the wall around Apple’s garden.
I have had a iPhone for 15 years, and I have only ever been able to back it up with iTunes on windows (as I will never buy a Mac).
Apple’s refusal to provide interoperability borders on criminal. I wish there was a better option.
I'm shouting into the wind here a fair amount, but I just discovered DeltaChat and ArcaneChat. ArcaneChat is available only on Android, but DeltaChat is available on iOS and uses chatmail relays. My family has found it to be super useful and effective. I don't think it's viable to convert everybody in my social circle, but I've been very happy with the apps and attachments, notifications, and general performance.
I'm considering running my own chatmail relay, although I haven't tried that yet.
Pixel is nice, in my opinion better than iOS, and more open for now
Doesn’t interoperability work two(Windows)-three(Linux) ways?
[flagged]
You mean the same Apple, who supports RCS, and historically supported open protocols?
As to iMessage, think carefully about the architecture, and maybe you can imagine why it is Apple only.
Have a look at https://github.com/libimobiledevice/libimobiledevice and iOS backup projects that are based on it.