Importance of OEM keyboards

[Cryptohygenic]

I have not had such experience neither have I heard of one falling victim through that means but it is very much possible that hackers can use such strategies to comprise our files including crypto and banking acocunts.
If a just existing malicious file could breach device security, I am sure malicious keyboards can do same too.
The very insecurity threats in the digital space is what has really made me not to be fan of using customized elements of device just for beatification because we don't even know what is hidden behind the software could be a danger to our device.

[GreatArkansas]

I'm curious about some smartphones, especially Android phones, because right now there are already a lot of brands, and some of these brands have their own stock keyboard app, and some of these have some "memory" feature or some dictionary or anything you can save, so I'm curious whether these are also safe? Like even it is comes from your phone, like a pre installed app (keyboard) from your phone.

[KiaKia]

I'm curious about some smartphones, especially Android phones, because right now there are already a lot of brands, and some of these brands have their own stock keyboard app, and some of these have some "memory" feature or some dictionary or anything you can save, so I'm curious whether these are also safe? Like even it is comes from your phone, like a pre installed app (keyboard) from your phone.

I believe I have an idea or two about what you are saying, under keyboard settings of my own android atleast you have an option to off the following if you want.

Spellchecker
Personal dictionary

The difference between pre installed keyboard and third party is that the preinstalled want to use a part of your phone memory as it's memory for storing your favourite words if you have the settings turned on compared to third party who will want to store them in the cloud.

Third party keyboards will ask for the permission to do so, this is why when approving permission one need to read them first to understand what the app is trying to do. Preinstalled app or keyboard won't ask for such permission.