Hold your thumb on the square and write one letter in the air.
write in the air
Hold the phone like a TV remote.
Hold your thumb on the square, draw one letter in the air, and let go. The line you drew appears, then the letter it settles into.
Wand: streamer mode first
tap·tap·tap·hold 5 seconds
until the light stays on — then press Wand. Switching the wand off puts it back in keyboard mode.