Following on from the original games, Pokémon Omega Ruby & Alpha Sapphire feature Secret Bases. However, these have been fully upgraded and integrated into the Nintendo 3DS hardware and software, and are now called Super-Secret Bases.
You can share your base through StreetPass and QR codes. You can also make "Secret Pals" when you go to other people's Secret Bases. You will meet a representation of their player. There, you can interact with these players and invite them to return to your base, to help build up a special amount of Pals. The Secret Pals features include:
Battling: The main feature is to battle the other players. It's not currently known what team they use, whether it's a preset one or based on their team at time of creating the QR Code/StreetPass.
Egg Nurturing: One of the special skills is the ability to make Eggs hatch quicker.
Level Up: Some Secret Pals will raise your Pokémon's level.
Decorations: You can receive various decorations from your Secret Pals.
The most exciting new feature is... GYMS! You have the ability to set battle rules which allows you to turn your base into a small gym with yourself as the gym leader!