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Vodafone Finds Brits Keep Mobile Phones for 4 Years Instead of 2
(www.ispreview.co.uk)
This is a most excellent place for technology news and articles.
No, there are unfortunately no truly workable Linux OSs for phones yet AFAIK. But there are plenty of Android-based OSs that work really well, and are usually maintained for quite a while, depending on the popularity of your device. Look into LineageOS, or Pixel Experience, to name a few.
There's ubuntu touch. I'm not sure how many phones that works on though.