  We revisit a recent bound of I. Shparlinski and T. P. Zhang on bilinear forms
with Kloosterman sums, and prove an extension for correlation sums of
Kloosterman sums against Fourier coefficients of modular forms. We use these
bounds to improve on earlier results on sums of Kloosterman sums along the
primes and on the error term of the fourth moment of Dirichlet $L$-functions.
