Is it necessary to have the Client v1.5.4 app on my S5?

A

AC Question

I'm trying to install an app and am being told that I don't have enough space. I'm going to buy an SD card, but I'm also wondering which of the default apps I can get rid of. This is going to be a really stupid question to some of you, so bear with me. It appears that Client is for gaming? Is it necessary if I'm not playing WOW on my phone? :)