You may use CentralPlanner on any device, as long as it has a browser and it is online. Just enter https://centralplanner.net in the browser and login with your regular email address and password. CentralPlanner adapts itself to the size of your screen, so you don't need to worry that it looks awkward on your Smartphone.
Every reservation you accept or change will immediately be available on your other devices as well, so you also don't need to worry about syncing between devices.