Player reach on a touchscreen very much varies from that of a controllers (and presumably keyboard and mouse, too. I believe keyboard and mouse has similar reach to that of a controller). This mainly happens when interacting with blocks.

Entities also have different reachabilities, but only in creative mode (~7 Touchscreen, ~4 Controller). There is no difference in survival mode.

Definitions:

Reach Horizontal - Max quantity of tiles of air that can be between the player and a block, and have that block still be able to be interacted with (See att. 1)

Reachable by sneaking over edge - Can the next tile be reached if the player sneaks over the edge of a block (See att. 2)

Reach Vertical - Max quantity of tiles of air between the player model’s feet and a block, and have that block still be able to be interacted with (See att.3)

Results

Steps to Reproduce:

1) Have instance(s) of Minecraft Bedrock running, where one is using a touchscreen and another is using a controller. (Switching between controller and touchscreen works too)

I personally did this by connecting a Bluetooth controller to my iPad and switching between touch controls and my controller, this is recommended.

2) Open the attached world (Either in the .zip or .mcworld, they’re the same), and begin experimenting with the reach on the platforms and pillars. If you record your results to the provided definitions, you should be able to recreate the tables (Vers 1.19.51)

You can also make your own world and set it up yourself, but I already made the test world so don’t waste your time, unless that’s your thing

Expected Outcome:

The controller should have the same reach as a player on a touchscreen when interacting with blocks, both in survival and creative. The interaction with entities in creative should also be the same

Actual Result:

The controller has a significant deficit in reach when interacting with blocks in survival and creative, compared to a touchscreen