iOS 13 and iPadOS includes both USB and Bluetooth mouse and trackpad support

Via AppleInsider:

Apple on Tuesday elaborated on mouse support in iOS 13 and iPadOS, saying both USB and Bluetooth devices will be recognized by the operating systems. The company made it clear, however, that the feature is designed specifically for a subset of users who have difficulty interacting with touch screen interfaces.
According to reporter Steven Aquino, Apple emphasized that mouse support in iOS and iPadOS is an accessibility feature, not a nicety created for the general iPad user.

So, on mouse support… Apple made clear to me it is an ACCESSIBILITY FEATURE first and foremost. Meant for users who literally cannot access their devices without a mouse, joystick, whatnot. As @stroughtonsmith found, it’s in AssistiveTouch menu.
Thread…
— Steven Aquino (@steven_aquino) June 4, 2019

More specifically, mouse support is designed as a stand-in for touch input, not traditional cursor control as found on Mac… “This is not your old desktop cursor as the primary input method,” Apple said, according to Aquino.

MacDailyNews Take: Again, we’ll see where this goes, but mouse/trackpad are obviously not meant to be the primary input method on the iPad. That’s why it has a multi-touch display.

Hello mouse support on iOS 13! It’s an AssistiveTouch feature, and works with USB mice. @viticci nailed this pic.twitter.com/nj6xGAKSg0
— Steve Troughton-Smith (@stroughtonsmith) June 3, 2019