Green’s Dictionary of Slang

(S.Afr.) an apprentice.

1985		Sun. Times Mag. 27 Oct. 10: All you need do is pop down to the local garage and charm the appies into lending you a couple of chamois leathers [DSAE].
1988		S. Gordon Under the Harrow 22: You blokes must teach him. He’s an appie.
1993		Natal Witness 6 Jan. 3: [headline] Jockey fined for hitting appie [DSAE].