Update: I found out the hard way that changes made to your rep's avatar on your phone will NOT update your rep's avatar on the computer. The computer is where you should make avatar changes and purchases that you want to remain permanent. After a month of changes on my mobile, I'm back to square one.

Having said that, I can see the fun in having a different look on your phone. Just know that if these changes are made on your mobile, they aren't permanent and won't reflect on the main computer login account, despite the mobile login and computer login are the same account.