You had a great idea and you launched it. Kudos! Now comes the challenging part of promoting it.
A sure way of getting early traction is to get influential users and early adaptors to use/review your app. If yours is a paid app, you need the promo codes to remove the friction of the app download.
Couple of ways you can do it.
Use Apple’s out of the box promo codes. You need to use iTunes Connect and sent out the codes manually. It is for a limited number of users (100 users per every version of the app).
Another good alternative is the Tokens. Tokens can be generated with one click inside the app and can be easily shared via email, Facebook, Twitter etc. You can test 5 tokens for free before buying it (unlimited tokens unlike promo codes). The good part is Tokens can be tracked to see if its redeemed or not.
From our experience of promoting paid apps, we found the $29 well worth the price.