1. If your Poke Ball misses the target and falls to the ground nearby - you can pick them back up by tapping on them to recover the Poke Ball and avoid wasting tons of Poke Balls on one pokemon!
2. If you walk away from the first three starting Pokemon at the beginning of the game you will have the opportunity to catch a Pikachu.
3. If you lock your screen, the game stops, so if you decide to go for a run and log some distance toward hatching an egg, you have to leave the app open and your screen unlocked. Unless…
4. If you have the Pokemon GO Plus device it WILL stay active and allow you to catch Pokemon, use Pokestops, etc. without unlocking your phone if you have the extra cash to spend on such things and don't mind walking around with a weird bracelet. For the rest of us, in order for the game to work you have to have it open and in front of you.
5. There IS a Battery Saver option that will help with this issue. What
Battery Saver does is turn your screen off but keep the app open when
you turn your phone upside down, as in the top of your phone where your
ear goes towards the floor. Pokemon GO will drain your battery like no
one's business so this is a neat feature to keep your game going while
you walk around and hopefully feel the notification vibration that a
Pokemon is near through your pocket.
6. The footprints show you how far away a Pokemon is. Every footprint denotes 50 meters of distance. A pokemon with one footprint underneath is is between 50 and 100 meters away from you. Three footprints show that the pokemon is less than 200 meters away. The grayed out Pokemon are ones that are not in your Pokedex yet.
7. If you select any Pokemon via the “Nearby” screen, you will target it and have a better chance of catching that species specifically.