The A2B Transport app is created for people who live work or study in Yerevan and have problems with public transport in their everyday life. If you're one of them you must download it.
With the complete lists of all public transports and the stops of Yerevan the app will help you to find those public transportation numbers (buses trolleybuses or microbuses) which you need.
Find the transport you need to reach your destination quickly.
And yes it's totally free and have no ads!