PROS: Easy to use interface means you spend less time marking Pokemon and more time catching them, Filters allow you to narrow your search for only the Pokemon that you're looking for, increasing your odds of completing your collectionc
CONS: The simplicity of the application means that there aren't a lot of features at this time
PROS: Very simple user interface has everything you need and nothing that you don't, Message other members of the same team to coordinate efforts in capturing Pokemon, Map feature allows you to tag your location at the time you post the message, allowing other players to find the same Pokemon that you've caught, possibly letting them find the rare Pokemon they need to complete their collections.
CONS: Simple interface could have more features for demanding players
PROS: Facebook authentication means you don't have to create and remember a new account, Find other Pokemon Go players on your own team to socialize with in your area, Simple to use and send private messages to people that you've added as friends
CONS: Independent application from PokeMon Go means that you'll be switching back and forth between the two applications while you're hunting, Simple interface doesn't have any advanced features that might be available in other dating applications