DAVx5 (formerly known by another name) is the only all*in*one synchronization solution for your contacts (CardDAV), calendars (CalDAV) and your tasks (based on VTODO). The app is easy to configure and integrates perfectly with your favorite calendar / contacts app (including the default apps). It can also be used separately, if you have CalDAV, CardDAV or just tasks.
Supported Android
{4.0 and UP}
Supported Android Version:-
Jelly Bean(4.1–4.3.1)- KitKat (4.4–4.4.4)- Lollipop (5.0–5.0.2) – Marshmallow (6.0 – 6.0.1) – Nougat (7.0 – 7.1.1) – Oreo (8.0-8.1) – Pie (9.0)