Discord: How to Boost a Server on Mobile

Nitro subscribers receive two Boosts as part of their subscription

Discord allows users to purchase Boosts for their favorite servers, which gives those servers access to additional content and features, such as additional emoji slots and an animated server icon. If you’ve purchased a Nitro subscription on Discord, you receive two server Boosts that you can use to instantly boost your favorite server(s). Nitro subscribers also receive a 30% discount on all future server Boosts. A server Boost costs $4.99 per month, but Nitro subscribers can purchase one for $3.49 instead.