Rondo

Drag a file, hold a key, drop it on a format. Free & open-source for macOS.

Drag a file and hold ⇧ Shift (convert), ⌃ Ctrl (tools) or ⌥ Alt (actions). Scroll to switch.
On a phone: pick a wheel, then press and hold a file.
Download for Mac ★ GitHub brew install --cask kstepanchuk/rondo/rondo