Ann: Share Purchase Plan, page-14

Login to Nabtrade website with browser on computer (I cant get what follows to work with Safari browser on an ipad).
Use the "Holdings" button to display your holdings.
For your chosen holding, there is a right angle bracket symbol ">" at right hand edge of screen. Click on it.
You will get a new screen which will have an item "Add cost base" which will be avail for any share parcels which were not purchased via Nabtrade eg ipo, spp, etc
Click on "add cost base" and you should be able to achieve what you want.

Dont think you can do this via the tablet app.

Hope this helps.