Freedom.to - Freedom is a productivity hack that lets you block apps, websites or the entire Internet on iPhones, iPads, Windows and Mac computers.
Typeeto - Use Mac’s keyboard to type on iPad, iPhone, Android, etc.
Stay Focused - More suitable with Google Chrome, this service enables you ensure you do not waste precious time on updating Facebook status or chatting with people.
Type2phone - Type2Phone: Use your Mac as keyboard for iOS devices
Serene - The macOS app to get your focus back
1keyboard - Type on your iPhone, iPad or AppleTV using your Mac keyboard