The Guardian has introduced a big update to their mobile app today which revamps the user interface, adds in some extra notifications, and a few more bells and whistles. Of course there's a full commenting system for articles, but users can also submit their own photos from around the world to share for contests and other themed stories. If you don't have time to read something, stories can be cached for offline reading later. You can shuffle around the sections so the most important and interesting stuff shows up first on your home page.
This is a great evolution of print, and seems to embrace the accessibility and interaction that modern readers are really looking for. The core app is free, but a £2.49 monthly subscription tier can remove advertisements, adds crosswords, and a special section highlighting curated content from The Guardian's 200-year content archive.
Any British readers big on The Guardian? How about those in North America? Which newspapers are you following on mobile?