Mac users interested in Telegram for os x 10.5 generally download:
Telegram is a desktop messenger that uses the services with the same name. The program has a nice minimalistic interface which nobody should have problems to use. In fact, it looks quite similar to the mobile app, and even its window has the shape of a smartphone. It has four main tabs: contacts, phone calls, chat and settings.
Telegram Desktop is the official application for a cloud-based messaging service. Since this tool has been designed for a very general public in mind, it is extremely easy to use, even for those with basic computing skills. It shows a list of your contacts on the left side, while the contents of your chats are available on a larger right-side pane. There are four interface styles to choose from.
Messenger for Telegram is a messenger app based on the MTProto protocol. Telegram is a messaging app with a focus on speed. It’s fast, simple and free. With Telegram, you can create group chats with up to 200 people so you can stay connected with everyone at once.
iCal is a simple calendar. It is able to work with Google and Yahoo calendars, as well as Microsoft Exchange. iCal can sync with iPhone and iPad, which can be handy at times. Use it to share your events with your friends, and see your friends' calendars in one place.