my brother works for a digital marketing company. companies contact him to get their app downloaded or new signups. Now the right way to do this is by promoting the app via various platform but there is a loophole which many of his colleagues are using. Basically, what they are doing is rather than spending the money on promotion they are somehow generating fake signups and downloads, then they use those fake account for few days or week to make them look legit. My cousin He asked me to find a way how they are doing this. PLEASE HELP ME

1st problem is each signup, and download should be from new device and ip address. The rivals are generating thousands of these fake accounts each month without getting caught with just one system and apps download with just 1 phone. I got that they are using VPN but How are they doing this in bulk even with vpn on single device and how they are downloading app on same mobile considering each new download requires new device id and they are producing thousand of these

I know this is not legal but with all of these loans and father illness please help me so i can earn some decent money and help myself out.