How would you know if your husband is sending making and receiving photos/videos from other women?

Any one experience this? What signs warnings or feelings did you have etc

I may be reaching far but he had a history search asking how to stop google syncing my photos videos. And months ago I saw some pics a girl had sent him - can’t see her face she was fully dressed but lifting her top up so you could see under boob she also wasn’t wearing a bra was wearing a white top with hard nipples poking through. It wasn’t one pic is was many of the same and the last pic you could just see some of her areole. Now his job is tattooing so I presumed she was showing placement of where she wanted the tattoo? Just found it odd she sent at least 6pics of it. I never asked him cos I know he would of said it was for tattoo.

Last couple months he been more attached to his phone before he would leave it down stairs charging now he takes it to bed with him ALWAYS. I did ask why he literally has his phone in bed with him now and he stated it cos I do. I reminded him I’ve always done that for the alarm but he never use to. So he said it cos he always on it so it’s habit now.

So tempted to search his phone if I ever get a chance but feel it would probably be the end of us! Whether that be cos I find something or he finds out I went through his phone…

Help