You can run Android tests and apps in the emulator or deploy them to your Android phone or tablet (with the required developer settings). With Robolectric, you can run Android tests in an ordinary JVM without the presence of an emulator or device.
If you have a Mac and an iOS device, you may consider using XCode for iOS development with deployment to your device. If you make this choice, you will be largely on your own if you run into problems, though.
These plugins are available through Help > Eclipse Marketplace:
Different software is required for each of these.