Apps

Pickleheads - An account on Pickleheads is required to participate in club events. This is where you'll sign-up for events, and where you'll enter scores and see matches during events.
It's free. They do offer some paid tiers, but you can just use the free one, unless you choose to upgrade for some of their very nice features. 

DUPR - This is the ratings system we use, so you'll need to have a free account here if you want to play in any of our rated events.  We run tournaments that report scores here, and sometimes we have events that are only open to players within a certain ratings range. After creating a DUPR account, you will need to link this to your Pickleheads profile (in the Pickleheads account settings).

GroupMe - The pickleball community in this area uses GroupMe pretty heavily as a group chat app, and GPC has our own group you should join.