I mainly use ImgBB since it has a good balance between being reliable and allowing people to look at the images without necessarily having to click on a link.
There's also Postimage, I used it for a while, but then some people told me they couldn't look at the pictures so I switched. Now I use it only in an emergency (like when ImgBB won't work for whatever reason).
I've also used Imgur, but it won't show images directly, so it's another last resort for me.
They all kinda suck. I use Postimages which has good functionality but apparently people in some countries can’t see that.
Best strategy is to find a service that gives you a free website (Universe works well) and upload your images to there.
Gravatar is too janky, I have no idea how people do it.
use postimg and use the link option for "direct link".
Use 
Example
I mainly use ImgBB since it has a good balance between being reliable and allowing people to look at the images without necessarily having to click on a link.
There's also Postimage, I used it for a while, but then some people told me they couldn't look at the pictures so I switched. Now I use it only in an emergency (like when ImgBB won't work for whatever reason).
I've also used Imgur, but it won't show images directly, so it's another last resort for me.
Postimg coming in clutch:
They all kinda suck. I use Postimages which has good functionality but apparently people in some countries can’t see that.
Best strategy is to find a service that gives you a free website (Universe works well) and upload your images to there.
Gravatar is too janky, I have no idea how people do it.
i use the one and only PostImages
reliable enough for me, but if you have alternatives its better to try them out first

Gravatar
i think i use steam or gravatar

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