Basically, several hairstylists handed over their phone to a customer that claimed she wanted to see their Instagram feeds. The "customer" then went through their phone and used their CashApp to send herself money from their account.
Situations where you hand your phone over to someone else may be a common problem if you are in a creative field where people want to see your work, so let's look at a few ways to handle the situation:
The first thing you can do is to make sure every application that can access financial data has a PIN number. For example, CashApp does not have a PIN to open the app, but you can go into your settings and set a PIN for sending money.
For even better security, most phones have an option to lock your phone to a single app. On iPhone it is called Guided Access and on Android it is called Screen Pinning. This would allow you to lock your phone to Instagram and prevent another person from getting out of that app to the rest of the information on your phone.
My first choice is to never hand your phone to another person, but if that is common in your business then these options should help you stay safe.