Excellent Upgraded V4.804 to V5.1 & switched from APG to OpenKeyChain without a hitch. Tested 4 signed messages so far. I'm liking it. I wish we could create rich content with images  or html but what K9 does currently  it does very well. K9 is well supported but they understandibly seem to prefer communicating via their google groups forum.
April 04 2016