Good construction, typical pitch and mod wheels, with 37 keys it has a convenient size for the desk (but unfortunately it doesn't fit in my bag for a little while!). It takes batteries and connects via bluetooth immediately and easily with the iPad where it plays on the very nice Korg Module and KORG Gadget programs for which codes are provided in the package! Negligible delay on bluetooth as long as you play with the program settings.

I mainly use it wired on the computer without batteries and without issues beyond the initial setup, it required a little search with the drivers until the computer recognized it, but after that everything was fine. This video helped me solve my problem https://www.youtube.com/watch?v=rVy2aqQm3U8&t=464s

The microkey air has become the main keyboard for my music setup. It is a very honest tool for anyone who wants to make music, I recommend it!