How are you tracking anonymous mobile users before signup to stop bonus abuse?

Hey everyone,

We’re currently hitting a frustrating wall with our mobile marketing flows and could really use some advice.

The Problem: When users click on a marketing banner, land on our bonus page, and eventually sign up, we often lose their anonymous session data. Since the system only records data at the exact moment they create an account, it’s becoming almost impossible to catch bad actors. We have malicious users who abuse our bonus system by constantly switching their IPs or clearing cookies before they finally hit "Sign Up."

Our Current Workaround: To stop this, we are trying to temporarily save device fingerprints and click events in the local storage. Once the user actually registers, we force-merge that local log with the new account data.

We’ve been looking into setups like the lumix solution to handle this device-stitching more accurately, but we want to know how others are dealing with this natively.

How do you smoothly link pre-signup device click streams with post-signup account data? What tracking techniques or tools are working best for you to prevent this kind of abuse?

Would love to hear your thoughts!