Slack was given a $1.1 billion valuation in October 2014--just eight months after launching the app for the general public. Today, it's valued at over $2.8 billion!

The popularity of this product has soared for numerous reasons, but the one that stands out is the engagement that the product enjoys from different communities that use it on a daily basis.

One such strong community is that of startup founders and aspiring entrepreneurs who're seeking a dialogue with peers or experts for guidance, validation, feedback and learn from experiences, etc.

How Does It Work?

Slack is a real-time messaging platform that facilities team communication in one place. It allows a single window for all conversations, but at the same time you can DM or direct message an individual for a private conversation.

You can be a part of multiple Slack communities and switching between them is pretty seamless. You can create or be part of different channels within a community. Channels include messages, files and comments, inline images and video, rich link summaries and integration with the services such as Twitter, Dropbox and Google Drive.

Here are some of the most active communities that you must be a part of to gain insights and learn from the experience of fellow entrepreneurs.

This community is founded by female founders for female founders around the world. You can join the community by applying on their website and paying a fee of USD 25. You will be refunded in case your application isn't accepted for some reason of in case you're not satisfied with the community experience.

I couldn't personally join and experience the community and provide feedback (for obvious reasons), but if the reviews are to go by, a female founder might definitely want to check this community out. Also, because I saw all the other communities mentioned below were largely male dominated.

With over 2,100 founders from across the globe, #startup facilitates discussions, Q&As, AMAs and conversations among entrepreneurs. You have to apply by filling a form on their website and paying a mandatory EUR 20. The money is refunded in case your application is rejected.

#startup is an initiative from the Startup Foundation--an independent non-profit, run by entrepreneurs, for entrepreneurs.

Founders discuss different topics and share great content, but the most active element of #startup is about giving feedback to one another. In the last couple of weeks, I've seen many entrepreneurs connect with each other over partnership opportunities between products.

It started as a community of 20 'kids' about 9 years back, 5 of who made it through Y Combinator, 1 a Thiel Fellow and several others launched startups that are successful businesses today. #Launch is a community of like-minded entrepreneurs, designers, developers and makers.

It is a place to collaborate, discuss new products, find work, get feedback, or even find a co-founder. Joining the community requires you to fill out a brief form to receive the invite once accepted.

#Launch has four channels: 1) #Launch: main channel for general discussions on products, business, ideas, etc, 2) #Code: for discussing all things related to programming, 3) #Design: for design discussions, UI/UX, photoshop questions, etc, and 4) #Sales: for discussing all things sales, customer acquisition, SaaS metrics, etc.

Being a part of the community for over two weeks, I've seen a mixed bag of messages ranging from business to personal banter. Conversations can get clannish at times.

A community of close to 3,000 'digital nomads' from across the world, it helps founders traveling to different locations and countries seeking a connect to answer questions such as where to stay, best places to work/co-work, good place to get local food or even to meetup with like minded peers.

There is a one-time joining fee of USD 35.

I don't get around to traveling as much as some of you may be, and so I didn't feel the need to subscribe to it. But I can totally understand the use for ones who are frequent travelers and need location-specific information.

This is a community of Bootstrappers, essentially entrepreneurs or those aspiring to be one at an early stage of product development. Bootstrapped Chat helps you find out what others are working on, share your successes or failures, or just "shoot the breeze" with other like-minded people.

There are over 370 members and while the membership is free, you do have to apply to become a part of the community. Conversations tend to be technical at times, owing to a largely technically sound member base that's building their own products.