I have been using the Kobo Touch for a week. I am sure many things have been mentioned already, but these are my thoughts.
1) Library has absolutely not structure. Please allow us folders (maybe use structure from file system?) and/or give filtering options by tags/author/series/...
2) Tags are not supported at all. It would be very userful to show them in library and enable searching by them. This could very well replace item 1).
3) EPUB offers metadata about series. I can not see that Kobo Touch exploits that. For instance, when finishing book one of a series, the device could offer to directly go to book two (if available).
4) I like the newly introduced clock. It reduces to the icon after a few seconds, however; please make it stay there (maybe as an option?). Also, please ofer 24h clock.
5) Definition and dicitionary lookup is great. Please allow us to add new dictionaries in whatever format. For instance, I learn Swedish so having a Swedish dictionary built in my Kobo would increase its value manyfold.
6) Many tools break down when viewing PDF (I guess because touch input is reserved for panning?). Please enable us to follow links and select text in PDF, too. Skipping to chapters also seems to be broken (sometimes?); maybe it depends on the PDF, though.
7) I searched for a word in a 70 page PDF. It took minutes, literally. Please improve that, if possible. I have had no such problems in EPUB so far.
8) Please add the option to disable page turn by tap. I use swiping and every accidental tap turns a page -- annoying!
9) On 1.9.11, home screen allowed fast library access. As of 1.9.16, all I can access are a few recently read and shortlist books. It takes far too many clicks to access something from library now. There is lots of space next to the big HOME menu item; please (re)add links to library and search there.
10) Please allow us to delete a book while reading it. Currently, we have to close and find it in the library again.
11) I tried the books from
http://www.hindawi.com/epub/ to check SVG support. While everything shows up nicely, the books take awefully long to open compared to simpler EPUB books. Please improve that. (Do you layout all SVG on load?)
12) You can apparently no longer connect Kobo Touch to a low-powered USB port with the new firmware. Why is that? Any chance to revert that back? It is ok if it does not charge (as quickly) but we should be able to transfer books on the device even from a USB hub without own power supply.
13) When turning the last page, Kobo Touch automatically returns to the library. This is particularly annoying when viewing one page documents (a map for roleplaying, some diagram...) as an accidental tap causes me to search for the document anew. Therefore, I propose that the device should ask what to do when the last page is turned; possible options: Go to library? Go to home screen? Stay here? Delete book?
Thank you for listening to your customers for your firmware development process!