Pokemon GO players are getting 3 months of YouTube Premium for free1
Unfortunately, not all Pokemon GO players are eligible for the offer, so unless you live in the United States, Mexico, Canada, Brazil, Taiwan, South Korean, Japan, Australia, Singapore, Italy, Great Britain, Spain or Germany, you'll not be able to redeem it.
It's also important to mention that this YouTube Premium 3-month free trial promotion is only open to Pokemon GO players who are not current YouTube Premium or YouTube Music Premium, have not been YouTube Premium, YouTube Music Premium, YouTube Red, or Google Play Music subscribers nor participated in a YouTube Premium, YouTube Music Premium, Google Play Music, or YouTube Red trial before.
The requirements are pretty demanding, but it's worth checking it out. Keep in mind that at the end of the trial period, you will be automatically charged the standard subscription price, currently $11.99.