I usually had a problem with my eyelashes, they can not be in curl shape any longer than 5 seconds. I have tried many different mascaras even waterproof but can't hold mine. I bought Dr. Mascara fixer from Etude House just because I watched the review for my favorite beauty youtuber, but not much expected of it.  
After trying it since my order was delivered to home, I was impressed how wonderful my lash was under this fixer. My eyelashes can hold on in shape even I just use 1 coat of regular mascara, not waterproof type, and it can make my mascara last longer. Highly recommend for anyone who is looking for the best mascara primer&fixer. Buy it now! You won't ever disappoint about it.
P/S: For eyelash primer: after curling the eyelashes, apply the Etude House mascara fixer first, wait a few seconds for it dry then apply the regular mascara.
        For fixer, wait for regular mascara dry completely then go ahead apply this fixer on top.