It really depends on what your goals and needs are as well - if you're looking for mass, you're better off forgetting isolation exercises; if you're looking for fat loss, anything will work (since it's NUTRITION that determines success here); if you're looking for strength, the compounds will still work better, with a couple of isolation exercises.
Why not stop doing a specific session for arms and just doing a couple of variations of the 'arm' compound exercises (dips and close-grip bench press, supinated pull-ups and bicep curls) at the end of one or two of your other resistance training sessions for a few weeks?
Otherwise, there's heaps of exercises - and variations of exercises - that you can do for your arms, including but not limited to:
Triceps - push-downs (rope, v-bar, straight-bar, etc.), reverse push-downs (using one arm or two), triceps extensions (standing or seated, using dumbbells or ez-bar, etc.), tricep kickbacks, dips (weighted, bodyweight, incline, etc.), push-ups with hands under chest (hands on floor, dumbbells, medicines balls, swissball, etc.), close-grip bench press, etc.
Biceps - curls (barbell, dumbbell, low-pulley, high-pulley, machine, ez-bar, etc.) concentration curls, hammer curls, preacher curls, reverse curls, supinated pull-ups, etc.
~Team APPNUT
