I just downloaded the app and I can't use it due to having a shitty cellphone.
Now to your question, it seems that all the data it needs to download for the game to run gets stored on your cellphone memory instead of the SD card (first thing I did was to transfer the game to the SD), dunno why it does that but it just does it.
Next time you need to ask something, there's a Q&A thread pinned for all your needs and questions.