From statements (i), (ii) and (vi), it can be concluded that Aman was the first person to reach the cinema hall. From statements (i), (ii) and (iv), it can be concluded that Dhoni was wearing the Yellow cap. Hence, either Aman or Boby was wearing the Purple cap and the other one was wearing the White cap. From statement (v), it can be concluded that Aman was wearing the Purple shirt while Boby was wearing the White cap. Further analysis leads to the following table:

Based on the given information we can make a table as shown below:

$\begin{array}{ccc}\text{Position}& \text{Person}& \text{Cap}\\ 1& \text{Aman}& \text{Purple}\\ 2& \text{Dhoni}& \text{Yellow}\\ 3& \text{Boby}& \text{White}\\ 4& \text{Chadni}& \text{Red}\end{array}$