iPhone keyboards are provided for each language, and for Japanese, there are two different input styles (kana input and romaji input). Third-party keyboards (keyboard apps downloaded from the App Store) can also be selected, so it is possible to register two or more types. There should be many users who register multiple keyboards and switch keyboards by tapping the globe button at the bottom left of the screen according to the character type to be entered.
Is it frustrating because when you register more than 3 keyboards, the keyboard you want doesn't appear? It doesn't always switch in the order of A→B→C, and if it's A→C→B or B→A→C, you might feel stressed.
On the iPhone, the keyboard switching order changes. The globe button is for switching to the "keyboard that was used just before", and has nothing to do with the order of "Settings" → "General" → "Keyboard" screen.
This mechanism makes sense. Even if the keyboard you are using is "Japanese-Kana" and you switch to "English", you can return to "Japanese-Kana" just by tapping the globe button. However, if you switch from "English" to "Emoji", you can return to "English" with one tap, so you need to tap multiple times to return to "Japanese-Kana". The number of taps increases only when you switch to the keyboard you use occasionally.
However, the principle of returning to the "previously used keyboard" is limited to when you type something after switching. If you tap the globe button without entering any text within about 2 seconds, it will be interpreted as a double tap, and you will be switched to another keyboard registered on the "Settings" → "General" → "Keyboard" screen. increase. It may be a trick not to feel frustrated when switching keyboards by not hitting the globe button in a hurry.