If somebody briefly had control of my cellphone, could they pull all the data from it?

Depends on if you’re password protected.
They can acccess and accounts that you saved the passwords.

They can use phishing attacks on any ill protected accounts. Like saving your banking machine with links.

Any account that you have your passwords safe, (Fluther, banking, ....) and not automatically logged in should ge ok. Unless you’re passwords are easy to guess.

Thanks, RDG. The phone was on, open. I handed it to them to take a picture from my roof. Later I found out they were bad guys, con men. So now I’m worried.

I never do any financial business using my phone, and I never put in credit card numbers. But there’s all the personal stuff, plus contacts, etc.

Eh, how bad guys, how technical, and how long if at all did they have it out of your sight?

If they were knowledgeable and equipped, and had a plan, they could try to download data while they had it, but they couldn’t get all the larger files without a considerable amount of time, if you had photos/videos/audio and they wanted that stuff. But if they knew what they wanted to get that was specific, they could probably do that pretty quickly.

They could also theoretically install some software that would do things after they gave it back to you.

Or they might have some other hack/ID theft in mind that involved doing a purchase and being able to get the PIN sent in 2-factor ID. But that seems elaborate and they’d need to set it up and know who you were in advance.

Or maybe create an account using your phone.

But those are bad-case-scenario theoretical possibilities.

If you don’t have any banking apps or credit card apps, then you should be ok.

I mean, they could access your contacts and what would they do with them? What else? Your email?

This is why I don’t have banking apps including Zelle or anything like that, or credit card apps on my phone.

From your brief description, I’m gathering these guys are fake contractors and just trying to get money for services they aren’t going to perform and run.
You are right to be concerned, but I don’t think these types of scammers have the mentality to steal your information from your phone. Good that you caught on and canceled the check.

I’ve heard there are grifters who go around trying to get business in roofing or driveway repairs. I think they’re fairly low level and not really trying to steal your phone info. I wouldn’t worry about that. if you gave them money, you may not see them or your money back again.