A contact record with a missing or outdated phone number is a dead end for a text message and no amount of good intentions fixes that at send time. Data Appending by RampedUp works from a base of contact details covering a large share of the population, filling in the gaps in a record before anything else happens in a Zap.

It sits in the middle of a Zap rather than at either end, so it does not send anything on its own and it does not wait for something from Mobile Message to start. What it does is make sure the contact details feeding into the next step, whether that is creating a contact, updating one, or sending a text through Mobile Message, are complete and current rather than whatever was typed in months ago.

For a business relying on SMS to reach customers, that matters because a text can only go to a number that is correct. Running an enrichment step before a contact is created or updated in Mobile Message means fewer messages bouncing to old numbers and fewer records that quietly go stale in the background.