5 Row Touch Layout Design Tradeoffs?


To date, I’ve kept my touch layouts to a maximum of 4 rows. I don’t recall why anymore, possibly it was a better fit some years back when I got started and mobile phones were physically smaller. I also try to adhere to no more than 10 keys horizontally.

I’m considering using a 5th row for a new keyboard where the additional row would solve a lot of spacing challenges. I note that the Samsung keyboard on my S22 also uses 5 rows (it has the screen real estate to spare), so I’m inclined to give it a go. The Samsung keyboard, including its predictive text row, and an emoji toolbar row below that, uses up to 7 rows total but consumes about half the screen vertically.

Is there any downside to using 5 rows (with will become 6 rows with a dictionary added) ? Are they problematic in any scenarios?

I imagine 5 rows is less friendly on smaller screens, but maybe the keyboard geometry scales down accordingly. Are Keyman touch keyboards guaranteed to fit on screen without being cropped off? Does the Keyman keyboard never consume more than half of the screen height? Or some other proportion?

Not wanting to clash with a good user experience, just wondering should I stay or should I row?