Update 8/15/16: developer very responsive. Ecg, vcg, measure & play all work independantly & as they should without crash warnings. The VCG screen can be printed by dragging the png to the desktop & printed from there, have yet to figure out how to get the ecg or measure screens to print. On ios they did print as a continous series of 3 pages, so hoping that it is changed to work similar to that. The exams portion of the app still appears to be MIA, but thats not a major issue, would certainly be nice to have though, but i’ll not doc stars for that, their ios ECG test app does a far better job of allowing you to identify individual conduction anomalies anyway (I’d pay another $10 if that were ported to mac, nudge nudge wink wink). Last note: the in app purchases screen is not present, I have looked for it, it’s MIA likely hiding with the exams. hoped for improvements: the click-drag calipers within the ecg screen that the ios version has Nigh on unusable on os sierra. None of the ecg, vcg, or measure buttons do anything but prompt a crash screen rendering the app fairly worthless. Seriously wish it worked. Will redact my review if I hear back from support with an update or solution.