Microsoft Teams Development

FIXME App catalog vs App Store

App typeScenario description
TabsSurface your content in Microsoft Teams.
BotsHelp users get tasks done in conversations.
ConnectorsPost updates from external services to channels.
Actionable messagingAdd enhanced interaction to your connector cards.
Messaging extensionsAllow users to query and share information in conversations.
WebsitesSurface enhanced content in your web pages.
ServicesEnhance your client applications with Microsoft Graph data via your web service.
Activity feedEngage users via feed notifications.
Calling and online meetings (preview)Create Microsoft Teams apps with bots that can initiate and participate in audio/video calls, route/transfer calls based on interactive voice response (IVR) flows, and participate in online meetings.

Source: YouTube

See also SharePoint Development