Ok, nudged by you guys in this discussion and by Sara65's discussion on PW I created an account and tried it daily for a week.
@oshogg I highly recommend pianomarvel - it has sight reading 'boot camps'.
Ok, so I was able to find them only after a week of searching. For others stuck in the same way, you have to go into the library, search boot camp as if it were the title of a book. Once you find "the book" you open and you click the "also available as a boot camp" button. I have not tried it yet. This experience just to say that the interface has many rough spots and it is not a polished experience (even though the interface looks neat and polished). Other examples:
- The documentation of the bootcamp is in a random google doc which you have to randomly find (rather than the normal documentation of the website) and it clearly feels as a draft (e.g. the MIDI setup should not be part of that)
- It is not clear what is the difference between the technique and method things are: they look the same stuff to me.
- Some other things, e.g. "ear training" (which is very good and deserves its own category) is considered part of the technique
- Ear training would be fantastic if the note stems would not give hints on the pitch ☹️
- In either or both technique and method there are flashcards. If you use continuous scrolling (which you want to use because is good for everything else), the flashcards are absolutely awful. Every time a flashcard appears you have to go to the settings, change the scrolling to flip pages and go back to continuous scrolling for everything else (if you don't forget).
- Some things in the levels of stuff that they present you appears too easy, some other too hard and I don't think that's me…
- Before you register it does not really tell you anything about the cost, if there is a free trail (yes there is), what does it offer, etc
Ok, so the above is the bad and the ugly (you pick which is which).
The good is that I like it a lot for sightreading and even just reading. Really nice (and I haven't tried the bootcamps yet). How is it better than a book? Well, first because it really forces you to move on, whereas on a book one always tend to "stay" and repeat, which slows down learning. Then, you get immediate feedback about your weakness. Very nicely, unlike a book, it seems to have an unlimited resources of stuff to read and perhaps (I am not sure) it adjusts the difficulty to your level. I've always struggled with that myself.
From a software perspective, they are continuously improving the underlying technology. For example now it works (only in the Chrome browser) without installing anything in the computer. That means it works in Linux and Chromebooks, besides Mac and Windows. For now it is only MIDI (which is okay), but they are working on using the Mic and audio to be compatible with acoustic pianos (a tough nut to crack because of how the wide-spectrum of the background noise, the harmonics of each note -- especially in the bass -- and other things interact).
It is different, but not very different from the app I had in mind myself which I discussed here. I'll write about the differences in that context.
In conclusion, I think that for people interested in practicing sight reading is worth your time for sure (and perhaps even your money for the paid account, depending on your finances and what you want to do). I'll surely continue working with it. It is also worth for ear training, but the stem "hint" problem mentioned above is really a drawback. For other stuff, I am not decided yet.