Start free. Upgrade when you want more.

Free gets you practicing; Basic brings back the cases you got wrong, so you can try them again.

The apps

Clinic: A few patients every day, each with an explanation.
Kardiograph: Learn to read the EKG on true-scale paper, then practice on a new tracing each time: rhythms, intervals, axis and more.
Auscultate: Heart, lung and bowel sounds. Listen closely, compare close pairs, and practice naming them.
Laboratory: Short courses on reading labs, starting with the fundamentals, then the CBC, BMP and liver tests.