Well here we are after a long way 3 seasons and enough drama to nearly split the internet in two. I am going to keep this review as simple as possible in an attempt to spoil as little as possible.
Two things out of many that make this show brilliant is the animation and music. Thankfully Equestria Girls does not disappoint in either. The opening sequence alone is a remix of the main theme with a lot of excellent movement to match the music being played, everyone agreed that it should be a replacement for the current opening of the main show. Daniel Ingram is a man of talent and it is no surprise that he does not disappoint. As for the main show the songs vary quite a lot in both theme and style. There are a few musical numbers with lot of dancing and singing.
Now comes the main plot of the movie. It is a bit on the weak side with the ending feeling very rushed. Personally I feel that rushed endings seem to be a recurring problem in the series too. One has to take into account the target audience and the fact that we may not get to see an extremely deep movie that Hasbro may feel it too over-complex for a younger audience to comprehend. Most fans of the show will predict what happens long before it occurs on screen. The journey getting there however is entertaining.
One of the subplots of the show was Twilight Sparkle attempting to adjust to her new body, both alicorn and human. In the human world she also has difficulty using technology on top of coping with the loss of magic. This comes out to a bunch of legitimately funny jokes that surprisingly do not get old as the story progresses.
The characters are well done both the main six and the many secondary / background characters that appear in the show. Without giving too much away they perform exactly as one may expect the pony versions to do. None of their actions felt too out of character or forced.
To summarize if you go in there expecting some great epic journey you won't find it. If you walk in the theater looking for some good laughs and colorful characters you will find it. They set out to create something that can be fun for the whole family and succeeded.
Lastly you should hang around for the ending credits as there is a bit of surprise there just for the fans.