Type2phone - Type2Phone: Use your Mac as keyboard for iOS devices
Keypirinha - A lightning fast and flexible keystroke launcher for Windows. No installation required (portable).
Typeeto - Use Mac’s keyboard to type on iPad, iPhone, Android, etc.
Alfred - Alfred is an award-winning app for macOS which boosts your efficiency with hotkeys, keywords, text expansion and more. Search your Mac and the web, and be more productive with custom actions to control your Mac.
1keyboard - Type on your iPhone, iPad or AppleTV using your Mac keyboard
Listary - Listary is a revolutionary search utility for Windows