Without naming names, there’s a well advertised grammar editing tool that’s available either as an app download or browser extension. This is something I’d value for a number of reasons (good grammar is important!) but I’m super cautious about anything I’m giving permission to watch what I’m typing.
Ideally, I’d prefer to select text and have it analyzed on-demand using on-device intelligence. I’m on a Mac and it seems like Pages isn’t cut out to check grammar. Also, there’s no way in heck I’m paying $30 a month for a subscription.
Edit: I just want to acknowledge my request for something I’d value and then saying I don’t want to pay for it. I would certainly pay for something if it met my needs but this function isn’t something I’d personally value at $30 a month or any monthly subscription ($30 a year sounds reasonable). Moreover, if there’s any suspicion of an application using my data for their own profit, they are not getting my money. So, in this case, for the sake of data privacy, I would prefer to pay for something (preferably once - grammar shouldn’t need updating).
This one is recommended by Mozilla
https://addons.mozilla.org/en-CA/firefox/addon/languagetool/
It DOES still need to send data somewhere to check
I don’t want to confirm details I don’t know, so someone else should probably explain more on if this is good/bad
It’s on my to-do list, but you can also spin up your own language tool instance so that your data never leaves your house, since it is open source: https://github.com/languagetool-org/languagetool
If you have a homeserver it can go there, otherwise you can also run it on your computer although I am not sure how much RAM it will use.
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You can run LanguageTool locally. While it isn’t as great as the paid version, I use this to check nearly everything I write for work in my native language, and in the other languages I speak
https://caderek.github.io/gramma/ is a cli spellchecker that has the option of installing a LT server locally. Not ideal if you are writing things with Pages/Word/etc., but a possible backup.