Based on our record, Sling seems to be more popular. It has been mentiond 7 times since March 2021. We are tracking product recommendations and mentions on various public social media platforms and blogs. They can help you identify which product is more popular and what people think of it.
Using Sling (https://getsling.com/) for a distributed CS team. It's working pretty well. We're spread across six timezones, been using it for five months. Free version's done well enough for us. Source: almost 2 years ago
If you want to try a free product, Sling scheduling app is good. You can google the reviews to see if that match your needs. Source: about 2 years ago
But I think you might want to look at some more dedicated scheduling software like Sling. Source: over 2 years ago
I've used Sling with my guard team. It's primarily a scheduling app, but it also has messaging functions. Source: over 2 years ago
I suggest https://getsling.com it's not open source but the free version is really good. Take a shot at it. GL. Source: almost 3 years ago
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