Slack's (WORK) app ecosystem has remained a key competitive strength as Microsoft (MSFT - Get Report)  continues seeing strong user growth for its rival Teams collaboration platform.

The company is now doubling down on its efforts to make its app ecosystem a selling point, by unveiling a slew of product improvements that collectively make it easier to both discover apps that integrate with Slack and access their features without leaving Slack's app.

On Tuesday, as Slack's Spec 2019 developer conference kicked off, the company announced it will support more feature-rich user interfaces for engaging with apps that are launched from Slack's main menu, as well as for engaging with pop-up windows that are used to share and collect information.

Slack also showed off a revamped app home page that lists both installed and recommended apps, and easier-to-use options for launching and searching for "app actions" such as creating a task for a team of Slack workers, filing an expense report or submitting a request to an IT department.

And with an eye towards better appealing to security-conscious enterprise clients, Slack announced it will both let developers ask for a more limited set of permissions for their apps, and give IT departments more visibility into why an app is requesting a given set of permissions.

The announcements comes a week after Slack unveiled Workflow Builder, an enterprise-focused solution that lets workers automate everyday processes such as making help desk requests or collecting information via forms. A Slack spokesperson indicated that over time, the company wants to expand Workflow Builder's capabilities to cover workflows that also encompass fully external software such as databases.

In a demo, Slack showed a new Google Calendar interface for Slack that (among other things) let users see their full schedules, pull up details about specific events, change their RSVPs for events and join meetings that rely on Zoom's (ZM) software. In another demo, the company showed how Slack could allow users of survey-creation software from SAP's (SAP - Get Report) Qualtrics unit to create and distribute surveys via pop-up windows appearing within Slack's app.


How Google Calendar will look inside of Slack going forward. Source: Slack.

Slack now reports listing more than 1,800 apps in its app directory, and claims its customers have developed more than 500,000 custom apps that integrate with Slack. The company also reports having nearly 600,000 daily active registered developers.

Slack's latest product announcements come at a time when its shares are trading about 40% below where they began in June, following the company's direct listing. A recent selloff in high-growth, high-multiple, enterprise software stocks has weighed on shares, but so have concerns about the long-term competitive impact of Microsoft Teams, which is bundled with many corporate subscription plans for Microsoft's Office 365 productivity suite.

In July, Microsoft reported having more than 13 million Teams daily active users (DAUs), up more than 100% from the same time a year earlier. And in March, the company reported that more than 500,000 organizations had adopted Teams.

Slack, for its part, recently disclosed having more than 12 million DAUs, up from about 10 million at the start of the year and 8 million in mid-2018. The company also reported that among paid customers, users on average spent "about 90 minutes per workday actively using Slack."

But while Teams' DAU count has surpassed Slack's, Slack still has a clear edge in terms of developer support. Microsoft's Teams app directory currently lists just 234 apps, or less than one-seventh as many as are listed in Slack's app directory.

And judging by this week's announcements, Slack is wagering that further strengthening the value delivered by its app ecosystem will help it convince enterprises that already have access to Teams via Office 365 that it's worth paying for Slack's collaboration platform.

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