Many transgender individuals seem to take pictures of themselves for a number of reasons. While many who are outside the community (and within as well) might often consider it as a form of narcissism, fetishism or something else, it is often much more than that. Although not exclusively a rule, I see the general trend that those individuals who have felt trapped in having to play an acting role in the play of their own lives tend to take pictures for reasons other than narcissism .
It's a way to capture the woman inside them and to have that with them for when they have to revert to playing their acting role in the gender they do not identify with. It gives one something to hold onto, ephemeral and intangible as it may be. It is a way to ask for critiquing among peers as they try to find and hone their true identity for the first time. It is a memory and a window back to a short period of happiness in having been able to express as one truly identifies and a picture can carry with it, the strength to make it through until the next time when one can express as their true selves.
It seems that those who begin to live full time as their true gender tend to rely less on "selfies" as they integrate in the greater world. Even the entire act of getting up in the morning, looking in the mirror and seeing the person they truly are in reflection back just becomes, for many, routine as the comfortability in one's self transfers to more meaningful and wonderful adventures in the larger realm of life.
Everyone who will comment on this will comment from their own perspective and it is a perspective that may one day change as we grow and mature. I, personally, have found that growth and pictures, except to capture moments in life, are no longer about moments needed to hang on tenuously to an identity that was once hidden. It is an amazing and wonderful transformation to behold. While it is not a superlative in any way, it is just as, if not more meaningful in the calm quiescence that envelops one as they finally feel comfortable in their own life and in their own skin. It is truly the most amazing feeling to behold and one that only a person who has dealt with in repressing their true identity can truly understand and appreciate.