  We study the $q$-bracket operator of Bloch and Okounkov when applied to
$f(\lambda)=\sum_{\lambda_i \in \lambda}g(\lambda_i)$ and
$f(\lambda)=\sum_{\substack{\lambda_i \in \lambda \lambda_i \text{distinct}
}}g(\lambda_i)$. We use these expansions to derive convolution identities for
the functions $f$ and link both classes of $q$-brackets through divisor sums.
As a result, we generalize Euler's classic convolution identity for the
partition function and obtain an analogous identity for the totient function.
As corollaries, we generalize Stanley's theorem as well as provide several new
combinatorial results.
