The Nielsen Mobile App is a free program available for iPhone users. Developed by The Nielsen Company, this app offers users the opportunity to contribute to research on internet and mobile device usage. By installing and using the app, you become part of Nielsen's measurement of the digital landscape and are eligible to earn rewards.

To begin, you need to sign up using the provided registration form or the information given if you were directly invited to participate. After submitting your registration, you can download the app to your smartphone or tablet. It's important to note that the app will not function and you won't receive rewards if you haven't completed the registration form or if you weren't directly invited.

Nielsen and their clients aim to gain insights into mobile device trends, including app usage, website visits, and time spent viewing content. Your mobile activity will be anonymized and aggregated with data from thousands of other panelists before any reports are shared.