3 years with OnePlus 3, I consider to upgrade.
What do you recommend

Mi Mix 3 is pretty damn great

Depends on where you live man. Seems like everyone gets this great selection of devices if they live anywhere outside the US ;___;

OnePlus 7?

I love Samsung's OLED screens, otherwise I find most models quite similar to each other. After the whole story with "Chinese brands will no longer get Android updated" followed by that "false alarm, keep buying Chinese phones", I've made a point to avoid them just in case. Plus there's that whole "I hate how China gives zero fucks about intellectual property" schtick.
I recently got myself the S10e because it's one of the rare premium smartphones (with OLED, optical camera stabilization...) with a 3.5" jack and a one-hand usable format, and I really like it.

Nokia 9, because of Android One

The newest one plud

How about a Google Pixel
And if you find it expensive then settle for a Samsung (The M series being the latest)
Do not go for Xiaomi,Oppo,Vivo etc. I don't trust the Chinese companies with my private data (opinion may vary from person to person, this is mine)

OnePlus 7 is a nice phone. I have a few issues with rotation on it being overly temperamental at times but my mum has the 7 Pro with the same issue so I think it is just a hardware problem.

Getting past that, no issues or problems whatsoever. Battery life is awesome, I can easily get two days out of it with light use.

No experience with One+ whatsoever, but I can recommend you to take a look at xiaomi brand. I am on my second xiaomi phone, very satisfied with both of them!

@RantSomeWhere
After last update it became laggy and sometimes slow.

@RantSomeWhere I remember once you recommended Nitrogen OS, or something?
I will give it a try..

@RantSomeWhere kernel 3.18? Not that I as a normie phone user would notice much difference but isn't that a bit old even for a phone?

@RememberMe the official ROM is using 3.18 too

@RantSomeWhere Well, it appears I can't root my phone.
I have a problem with the charging port, the phone cannot be detected by tye laptop.
Unless there is a way to root it with PC.

So bad.