Answer: No I+ cannot be called a Lewis base.
Step-by-step explanation:
According to Lewis Theory, it defines an acid as an electron-pair acceptor and a base as an electron-pair donor.
In terms of Lewis basicity, Iodide ion (anions) has the more readily available lone pair electrons for donation since iodide ion is less electronegative .
With the help of the net electronic structure one can understand the answer of the question, because we need to study the I+ ion (cation) structure.
Lewis acid is therefore any substance, that can accept a pair of nonbonding electrons.
From the picture below I+ is most likely ready to accept electrons not to give from it 5s orbital to become stable.