Wallaby is all about motherly love.
You have to play the antipodean mother who is trying desperately to get to her poor baby, at the top of the screen. Making life difficult are the 'evil' monkeys who scramble about the screen killing you, if they touch you.
You can punch them, if you are close enough, or jump over them - but they are full of nasty habits, they eat apples and then throw them at you. These too cause fatal injuries and have the most interesting flight patterns which are difficult to avoid.
Add to this the fruit that you can collect on the way and the bell to ring for more fruit and the whole game is revealed.
In essence it's like Crazy Kong, but there is sufficient variation to make it interesting. Although the screens are well laid out, they lack colour and flair. In fact, the whole game is likely to pale after a few days and lacks that vital extra quality to make it great. Good fun though.