Yes. You can log in to your account on any number of devices. Data synchronization protects your account from overbooking. When logging in to your account on different devices (Android, iOS), make sure if you have an active Premium license for each platform (Android or iOS).
If you have an active Premium license for only the Web + Android package and you log in to your iPhone or iPad (iOS) account, your iOS application will operate in the free access mode.
In order to use your Premium access on both platforms (Android, iOS), purchase the Web + Android + iOS.a package.