My dad has an infinite budget to buy a smartphone but What do should he buy?

[DavidAlexandrovich]

he has rather large fingers so touch screen although favoured, would not go with him well. He gets confused really easily but thinks its time to move on to a smartphone. So what do you think he should get?

 

[NoraCat]

Since you say he gets confused easily, I would choose based on ease of use. The easiest to use smartphone is the iPhone, so that's what I would recommend.