Sprint is giving promo codes through MyTrainerRewards

Sprint is currently awarding a promo code redeemable in the Pokemon Go App (Android only) good for 2 Incense, 5 Great Balls, 1 Lucky Egg, and 15 Pokeballs. To get the code, you simply have to enter their Pokemon Go Halloween sweepstakes on MyTrainerRewards.

Some technicalities:

• My Trainer Rewards is USA only (Sprint is only paying for the sponsorship in the US. Cannot verify if there are any measure to disallow members completely.)
• You DO NOT need to be a Sprint customer
  - You need upload a photo of a 'Hoenn Region Ghost type Pokémon' found in a Sprint store. (You can actually upload anything if you just want the code but I don't endorse this.)
• You might need to verify your phone number but probably not.

In order to enter, log in to your account and go here: https://www.mytrainerrewards.com/app/catalogue/pokemon-go-halloween-celebration

Click Redeem. The code will be send in an email to you.