I've got both the android and iphone version of chinese skritter. I noticed they choose/calculate which words are studied vastly differently. i study HSK 1-4. Both versions will calculate the same quantity of words to study, however, android will bring up a group of words excessively repeatedly, until moving onto another group. The iphone however seems more clever in it's calculations and chooses words I need practice on (based on my previous low scores on those words) at a widely varying selection. The result is on the iphone, i study more words i don't know (opposite on android) in the time given, making more effective use of the spaced repetition method.

Are the developers aware of this and do they plan to fix it?

Thanks :)

I have noticed this with the Japanese Andriod Skritter as well. The spaced repetition is a bit odd.

The scheduling is done using different algorithms, yes. Would you say that when the Android app is bringing up these same word groups and over, it's because you've been getting them wrong over and over, or is there something else about them that's distinctive?