Income $600 and above is subject to income tax. For instance, if you win prizes off the radio, and they total $600 or more for the year, you have to pay taxes on your winnings. Same deal if you win big at the casino.
Now, if you use VenMo often to pay friends for dinner tabs or concert tickets, don't worry. The I. R. S. will be looking at people who are earning $600 or more of income through the apps, income that hasn't previously been subject to tax.
The problematic part will happen when the cash apps start sending you 1099 forms. It's on the tax payer to notify the I. R. S. whether the money received was income or other.
This kinda sounds like a headache, huh?