Im gonna use this phone for couple of years. The best choice is OP5 or Samsung S8?

[AC Question]

I'm a camera lover but all my past mobiles had broken screen as I'm so careless with Dem.

 

[belodion]

You're asking which is better, only in respect of Camera? What is important to you in a camera? Some prefer photos to be like this, others prefer them like that.
https://forums.androidcentral.com/showthread.php?t=409154
Also, given carelessness, you would find it surprisingly easy to break the screen on pretty much any phone.

 

[KyonCoraeL]

I would highly suggest purchasing a tempered glass screen protector and a case. Those are worth their weight in gold. I find even having the smallest case and a glass screen protector helps alot. Often I find myself with a cracked screen protector after a few months but at least it's not the screen.

I don't think you can go wrong with either phone. I have heard that the Samsung S8 has better low light performance.