Thing 7 is content saving and sharing, or social bookmarking. This is another instance where my old iPod is not sufficient for either of the choices offered on the 23 things website, so I went looking for other options. I Googled social bookmarking apps for iOS, and read some articles. I found that there is no shortage of apps out there, but most of the ones I looked at are not free, or are no longer in operation, or require higher versions of iOS that my iPod won't support. I decided on Pearltrees, which has a free version (upgrades available for a price) and only requires iOS 5.
I've never used social bookmarking before, so it's hard to know what features I would find most useful. But Pearltrees sounds pretty good. It allows users to "pearl" websites, photos, and notes, and to organize those pearls into trees for easy access. Users can also see related pearls from other users, and "pick" them to add to the user's own trees. In the free version all pearls are public; privacy can be had in the pay versions. I would prefer to be able to choose whether my trees are public or private, so I don't like the fact that Pearltrees makes you pay for that choice. But I doubt I'll be using the app much, so I guess it's a moot point.
I did not find it very intuitive to use. The app's own information on how to use it was long on concepts and short on specifics--I was able to easily add websites and notes, but once added I never saw them again. The appearance of my home page did not change, except that once I added something it would show me a "related" icon, which did nothing when I tapped it. I couldn't see the pearls I had added, and could find no information as to where they were supposed to be. The app includes something called the dropzone, which I believe is where pearls are stored until they are organized into trees, but I could not see any way to see the contents of the dropzone. So I could not organize my pearls, and also could not access them in their un-organized state. I don't know what Pearltrees did with them, but once I added them they seemed to disappear.
There were a couple of instances where the app said to use a tool supposedly visible onscreen, which was actually not. So it may be that the app simply doesn't work properly on an iPod touch, even though the app store claims they are compatible. I still consider that attempting to use it has been a good learning experience.