  The BFKL and the unified angular-ordered equations are solved to determine
the gluon distribution at small $x$. The impact of kinematic constraints is
investigated. Predictions are made for observables sensitive to the gluon at
small $x$. In particular comparison is made with measurements at the HERA
electron-proton collider of the proton structure function $F_2 (x, Q^2)$ as a
function of $\ln Q^2$, the charm component, $F_2^c(x,Q^2)$ and diffractive
$J/\psi$ photoproduction.
