[GraemeJ]

All things considered, an IOS version looks to be some way in the distant future.  My advice would be to buy an Android tablet, with a screen size that would suit you (although I would recommend a minimum of 10").  They're not expensive - lots of cheap Chino knockoffs around and they all seem to work well enough, as long as you consider it as a tablet for MSP only and don't fill them up with loads of other apps.