Do I need to replace email with product announcements inside the app?

Not necessarily. In most cases, you should not replace email entirely with in-app product announcements—you should use both, because they serve different purposes.

Use in-app announcements when:

• You want to reach users while they’re actively using the product
• The message is time-sensitive or tied to a feature workflow
• You want higher visibility for things like:
  • new feature launches
  • onboarding tips
  • release notes
  • upsell prompts
  • policy/product changes that affect the current session

Keep email when:

• You need to reach users outside the app
• The message is longer or more detailed
• You want users to have a record they can refer back to
• The audience may not log in often
• You need a channel for:
  • major product updates
  • re-engagement
  • account/security notices
  • billing and legal communications

Best practice

Treat in-app announcements as a supplement to email, not a full replacement. A good pattern is:

• In-app for awareness and action
• Email for follow-up, deeper explanation, and reach to inactive users

Rule of thumb

If the announcement matters only to people already in the product, use in-app first.
If it matters to people whether or not they log in, keep email in the mix.

If you want, I can also help you decide based on your specific product type, audience, and announcement type.