Starting from version 2.41, you should use versions 3.XX and above.
From our experience, the versions 3.0.1 and 3.1.0 have problems with big datasets using Options Combinations (the fields filled in disappear after filling).
The version 3.0.0.2 is better for datasects but has issues with some program rules not being triggered for tracker Issues.
The version 3.0.1 has problems with QR Codes sharing:
QR Code Sharing Feature does not work as expected in Android 3.0.1 - Support - Assistance technique - DHIS2 Community
Also the version 3.1.0.1 crashes when using “Text with multiple Values” Value types.
See here:
Android App 3.1.0.1 crashes when using "Text with multiple Values")
We are still testing the last version (3.1.1) but I would say this is probably your best chance to have both datasets and program rules working properly, although I am not able yet to confirm the data set issue has been resolved.
Hope this helps a litlle.