Calendly gives you a simple and elegant way to schedule your meetings without having to do a to and fro conversations on an email or chat. You can simple see it as a new generation assistant to people with lots of meetings like CEOs or sales guys. Your meetings will directly be added to your calendar and hence it is easier for anyone to know your availability. It can be directly added to chat and emails with your available time slots and once somebody selects a timeslot it will get automatically scheduled so that no one else can book it further. It will also send you automated reminders so you do not miss a meeting.
Calendly is free for users with 1 calendar and 1 event type where you can schedule unlimited events. The pricing plan starts from $10 per month per user ($8 if billed monthly) where you will get 2 calendars per user and unlimited event types.
No, it does not have an iOS or Android app yet. It can only be used from Desktop or mobile web currently.
Once you signup for Calendly using your Gmail account, it will automatically get connected to your Google Calendar where it will be able to read all the events where you are busy and all those times and dates are removed from your scheduling time. You can also directly connect your outlook account and Calendly will start reading your availability from your calendar events.