Lets analyse this a second.
On the left tells you what the game is, the legendary Pokemon being the symbol for the game makes sense. Then we transition over to Lilly, the main character who the plot revolves around entirely.
Then we have the free to play symbol, what is free to play exactly? well, we have a gorilla-like character to point us in the right direction... but not to the title, but instead to Lilly. As per most adverts for primarily male gamers, the focal point of free to play games is often directed at the female character.
As Tarvaax said, its essentially to enable a night/day switch which can speed up capturing Pokemon.