Since you are already using the stock apps on your phone and they have the features that you need have you considerd EteSync?
EteSync integrates seamlessly with your existing apps. All you need to do is sign up (or run your own instance), install the app, and enter your password. After that, you will be able to save your contacts, calendar events and tasks to EteSync using your existing apps, and EteSync will transparently encrypt your data and update the change journal in the background. More security, same work-flow.
I think that this would be the closest option that would fit your needs, let me know what you think 