I presume you mean the A330 mission system, vascodegama?
The problem with a 'GPS enabled iPad' is that, unless it had inputs from other aircraft systems (e.g. fuel quantity, air data, nav system), it would require manual updating - which is error prone unless the entry is cross-checked by another crew member (a bit like Oceanic waypoint insertion checking) - which increases workload.
But it's a cheapo option which could be provided very quickly - the current A310 mission software works fine in 'planning mode' on a Win8.1u1 platform and adding a GPS card / app plus a manual fuel entry window for in-flight use wouldn't be difficult.
Incidentally, the version of the A310 system you saw all those years ago was really quite basic compared with the latest system.
(The 'Dalton and bits of string' quote came from someone we both know well!).