Olympus OM-D cameras are now supported with the the Timelapse+ VIEW Intervalometer running firmware v1.8-beta31 or newer. Tested so far with the E-M5II, it's expected to work with the E-M1, E-M1II and E-M5II. Other Olympus cameras are not supported. The first release includes support for exposure ramping (auto day/night/day) and liveview. Focus Ramping support is possible and will be added in the near future.
Update: It's now confirmed working with the E-M1 and E-M1 II as well, with experimental focus ramping support as well!