Whats the use for POA app on Ledger Wallet?

Hi all,

A few months ago, when I bought POA tokens I have store them using my Ledger wallet on MEW. Today I notice that Ledger has its own POA app. I have installed and try to access my POA tokens on MEW using both the Ethereum and POA apps on Ledger and both work exactly the same showing the same POA tokens balance and accounts.

So, about this 2 questions:

1- What is the use for the Ledger POA app if we can manage POA using the Ethereum app on MEW? Why the 2 apps?

2- As said before i bought my POA tokens several months ago and stored on MEW using Ethereum app on POA network. Do I need to do anything, like swap or exchange so my tokens are valid?