I bought the leuc and was told it is 2 to 3 years old. The azureus should be about the same age. Sorry about the bad pics, I could not get a good picture of them in a ff cup and they wouldn't stay still for me.
If I had to guess, it looks like both of the frogs are female. However, if the leuc was a little bit on the chubby side, it could be a male, and the azureus seems a bit on the small side for a 2-3 year old (or you have huge hands).
Below are some links to articles on how to visually sex dart frogs. They include pictures and such, so it might be easier to look at them, then observe the frogs in person.
Thanks Zach, my hands are on the large side but that is the azureus hunkering down, it is normally standing tall and off the ground and looking almost twice that size. The Leuc is as small as the pictures make it look though, I was thinking male because of how small it is but it is kinda on the portly side so I am torn on what it is, I have only had them a couple months, but I have heard no call from either one. I will check out the website but if anybody else has any guesses I would appreciate it.