... boils down to five key components: Your app Backend for data storage (DB or DWH) Product analytics (Firebase, PostHog, Amplitude, Mixpanel) Mobile Measurement Platform (MMP) e.g. AppsFlyer or Adjust Emailing tool/ Customer Engagement Platform (CEP) Mailchimp, Launchlist, Airship, Braze, MoEngage, etc., depending on where you're at in relation to launch. This stack gives you full-funnel visibility, cross-channel orchestration, and user-level performance attribution all without overcomplicating things. What s not essential: CDPs, social tools. CDPs came ... ... stack that ll take you pretty far. Most, but not all free but you can make a free version of the below if you need to be scrappy: AppsFlyer (MMP) for attribution Brevo/ Mailchimp/ ConstantContact/ or Airship / Braze / MoEngage