Bark is The social app for dogs that helps you too:
1) Find out who is out on walks when you are with realtime mapping showing you all the dogs near you
2) Have doggy conversations withe friends
3) Set your mood for your doggy to let others know if they are happy, playful or need some space
4) Mark your lady dog in heat, and send poop bag alarm
I recommend Bark to all dog lovers
Pros:I can walk with my dog without stress of meet danger dogs
Cons:would be awesome if app would support cats