[imunolion]

There are some better input methods for Japanese, and they are not available on smartphones.

SKK

What you are talking above is phrase-wise conversion. However, using SKK can easily distinguish "感じ" and "漢字" by "KanJi" and "Kanji", by explicitly specifying where the conversion starts and ends with Shift key. SKK can massively reduce the conversion candidates, so that people can faster obtain converted sentences.SKK is a good input method, but doesn't exist for smartphones.

T-Code (or TUT-Code)

We also have t-code input methods on computers but not on smartphones. It assigns 2 key strokes into one letter(kana or frequently used kanji) directly. For example, "kd" will type "の" and "is" will be "東". This input method is also very efficient and boost input speed, however it is designed for physical full size keyboard with 8 fingers. Its users can't do the same with software keyboard because they remember the key strokes with fingers.

[peterburkimsher]

If anybody is interested in a Kanji dataset for improved input methods, please check out the 52,835 characters I gathered.

https://blog.usejournal.com/making-of-a-chinese-characters-d...

I made my own input method for Chinese Hanzi, which decomposes the characters and lets me find characters based on their IDS codes. It also predicts words both forwards and backwards (in case you don't know the first character, but do know the second).

https://pingtype.github.io