I mean, you say "is this it?", but the multi-language support of literally all other Android keyboards I've used are basically unusable. Take Google's default keyboard, it requires you manually switch languages for swiping and predictive text to work. But that's completely unworkable for the way multi-lingual people end up actually typing texting. I swap back and forth across languages, even if just for 1 or 2 words and having to explicitly toggle languages is a MAJOR speedbump in typing.
Swiftkey just lets me auto-complete/swipe in multiple languages seamlessly. Want to swipe 1 English word inside a completely Dutch sentence? No problem. The reverse? No problem. Using Google's keyboard the same way is endlessly frustrating.
What do you mean when you say "Google's keyboard"? I use Gboard and frequently swipe sentences which mix Spanish and English just fine. You enable "Multilingual typing" on the specific keyboard and then tick off languages from other installed keyboards to enable them. Maybe you haven't tried gboard for a long time?
There's some internal matrix of "Supported" clean movement, mostly between languages with an extensive shared vocabulary. You can enable Multilingual Typing theoretically anywhere, but it only really "works" among languages that share a layout and character dictionary.
But if you need to loanword a non-common word from English into another language (e.g. Hebrew), Gboard just can't do it. If you change character sets, you change entire dictionaries. SwiftKey has a unified dictionary among all languages and makes a best guess approximation based on the current language selected and then tries the other languages you have configured.
This means that if you're going along in, say, French, but then need to reference a word in Hebrew, you can swipe over to Hebrew, bang out a word, then swap back to French, type words in English (which get autocorrected in english) and then continue in French. This isn't really feasible in Gboard without a lot of back and forth.
Maybe Google updated the Gboard since the last time you used it, but it definitely predicts from multiple languages in the same sentence for the last couple of months at least.
The default one on Samsung will let you select multiple languages under "Suggest text predictions". Not sure if that's a clone of the default Google one, but I had so far assumed so. Seems to switch decently between Dutch and English, for me.
Yeah. Though decently is not the same as excellently.
Written on a SwiftKey keyboard used to write English, Swedish, Danish and Icelandic with minimal issues.
Though to be fair, I think the stock keyboard is probably almost as good these days and that the difference is that my SwiftKey keyboard has been trained on my writing for several years.
Though I have no idea more than that I quickly get annoyed when I try to type on the stock one.
I use GBoard with both English and Spanish installed, and I don't have to manually switch anything to swipe in both languages, or get predictive text in both languages.
Swiftkey just lets me auto-complete/swipe in multiple languages seamlessly. Want to swipe 1 English word inside a completely Dutch sentence? No problem. The reverse? No problem. Using Google's keyboard the same way is endlessly frustrating.