This is a very useful and fun app for learning to read rhythm notation in music. I also find it very challenging.
There are all kinds of options for making it work for you like being able to create your own patterns or selecting individual bars to repeat and practice. They will also have two measures in sequence that sound the same but are noted differently, with one representing all beats (the way it should be) and the next not representing all beats (the way it often is noted in sheet music).
I almost gave it four stars because I think some of the setup screens are a little confusing. But overall, this is worth much more than it actually costs when you factor in how rapidly your skill level can improve. So I think it deserves five.
sfmonkeyc about Rhythm Sight Reading Trainer