In the Android emulator, a long keypress on the "keyboard" will pop up a selection of variants on that letter to choose from. A long keypress on the same key in the soft keyboard displayed on the device itself (still in the emulator here) will also pop up a selection of variants on that letter to choose from. But the two lists are different -- for example, long keypress on "a" gives nine options when pressing the keyboard, and seven options when pressing the IME key. (The a+ogonek and a+macron are missing.)
I assume the keyboard in the emulator allows the developer to simulate things going through keyboard event handling and the keys displayed on the device's screen allows the developer to simulate things going through the IME instead, but does anyone know why the variants displayed are different?