Best practices to market apps?

Hi all,
For a soon to launch initiative I’m thinking about ways to market stuff. Of course, the Glide marketplace is fine, but in ideal world I’d be able to do stuff like:

  • Discounts. Give people cheaper versions by giving away codes.
  • Limited amounts of give aways. Say stuff like: the first 100 are for free.
    As far as I know that’s not included in Glide, but I was wondering what are best practices you use to market apps?

One of my apps (my very first one, in fact) is a Fantasy Golf app.
One incentive I have introduced just recently is to offer free credits to my users if they invite new users who sign up and participate. I’m yet to see how effective it will be, but I have seen quite a few invites go out already, so early signs are promising.