1. Free with ads
   1. Positive
      1. Data collection
      2. Gains users quickly
      3. Growing industry
   2. Negative
      1. Annoyed of ads
      2. Comprise experience
2. Freemium
   1. Positive
      1. Build a large user base
      2. Try before you buy
   2. Negative
      1. Few features
      2. Too many features for free
3. Paid apps
   1. Positive
      1. Revenue with every new download
      2. Engaged users
      3. No in-app ads
      4. Motivate developpers
   2. Negative
      1. Competition from free apps
      2. App stores take revenues
      3. Less downloaded
4. In-app purchases
   1. Positive
      1. Profits without risks
      2. Engagement of the users
      3. High profit margin
   2. Negative
      1. App stores take revenues
      2. Model had a bad publicity
      3. Have to be more transparent
5. Subscriptions
   1. Positive
      1. Experience all the features
      2. Continual revenue
      3. Loyal users
      4. Motivate developpers
   2. Negative
      1. Determine how to place the paywall
6. Sponsorship
   1. Positive
      1. Related to the apps
      2. Revenue for devs and promos for users
   2. Negative
      1. Not as tested as the others